I know people don't like to create accounts, but Larian seems to be doing fine when I created the vault account(for their prior kickstarter redeem etc.) It doesn't work with launcher and I contact support to then know they have a new system so they can link steam/twitch/gog for their game specific feature(cross save and twitch integration). So if you ever want to do a session in the future using the twitch integration, you would have to register account to be able to link and use that. It lets viewer check character build/inventory and quest logs, so you can have like 3 viewer like your buddy playing together while you control the choice, your buddy can vote for decision making or direct their character's combat choice. At worst you can be the only viewer to your stream and just use it as a 2nd screen to have over view of character build or inventory.
OP is concerned about their privacy, rightfully so. Them requiring you to make an online account after you have purchased the game is entirely unjustified. They could already tie information to the account with which you purchased a licence.
Connecting Twitch and whatnot would work against your privacy: even if Larian does not do anything bad, they will share data with these connected accounts.
Yep I understand those and just saying the obvious reason why one might want to create account, and you can skip or disable launcher entirely as mentioned in this thread.
Cross save( especially between consoles<->PC ) requires linking accounts, Larian disabled it now because of a hotfix bug since PS5 version is not released yet and causing PC player issues.
And I honestly don't know what kind of threat Twitch has over your privacy on a fresh Larian account. See here is a brief breakdown what they can see:
Larian: they now know I have a twitch account, potentially my twitch account's email address.
Twitch: they now know I have BG3, on top of Rocket League and some games I used too stream with a friend. And I am on that garbage tier cause the account is a burner(to sign up stuff that might get spam mails), I never spent a dime on twitch, my user experience data is probably worst since I only go straight to the channel I want to get drops with and never "browse the recommendation". BG3 I had to go to the game's page and click on the drop enabled one then afk for 2 hours then I just close it.
So unless there is some secret tech I am not aware of, please do let me know why and what else might be shared that have threat to my personal info/privacy.
Larian has access to your game saves, and so if they wanted they could deduce your play style and so parts of your personality from it, things which are useful for targeted ads and other things.
If you say Larian can be trusted, this is probably not much of a concern, I mention this only because of Twitch. Twitch relies on data mining, and if Larian analyzed your saves for things like above, they they would have things to trade. But I have no idea about BD3, maybe they know more significant things than that.
With Twitch, it's a little different.
First, they obviously (because they have personal recommendations) collect information on your interests, like what content do you prefer, but as you said this does not apply to you.
However Twitch also has several mechanisms for getting you to give up your phone number or email address: they don't support standard time based 2FA authentication, instead they can only send codes in SMS or email, and 2FA is required if you want to stream (even only once) or get your own API key to be use for archiving programs and such using the twitch API.
The problem is not actually connecting Twitch with your Larian account, it is connecting it with anything at all, and if the other connected account also does data mining then it's even worse, because if the collected information gets to Twitch, they will probably be able to tie it to a real world identity (like a phone number, payment account, or a honest primary email address (that may even include your real name)), but also some history on how easy is it to get you to spend money, or just how easy it is to get your attention, and then pass it all off as something even more valuable to "business partners".
Also, I'm not actually sure if Twitch would bother with support for connecting accounts of services from which they can't extract much value.
So my main point is that I don't know about Larian, but Twitch is only in it to gain something from it, and they would scoop up whatever Larian makes available.
I am pretty sure they can't give information to 3rd party other than the necessary part since they are EU based. And usually when you link account, it's where you started the linking asking information from the target platform. In this case it's Larian asking Twitch for auth so that a Twitch user is linked to a Larian account so they can access your viewing time and distribute the drop. (No, you don't need to link if you are just viewer and not wanting the drop, it's the streamer needs to the twitch integration like the voting extension, etc. I still have mine disabled. ) It's usually outlined when you try to link and it will show what's requested during the linking process.
Maybe I am not really careful from your perspective, but I have like 5 gmail/yahoo/proton email accounts that does different things depending on the information I want to share with the registered site. Didn't go crazy like some one site per e-mail account, but it's sufficiently safe over the years. I have never had a data breach/account stolen with my practice so far. (or getting unwanted emails on my banking/work related account.)
As for hiding my identity entirely from internet it's probably a bit too late to the big corps cause stupid me registered a FB like every "dumb fucks" that did, oh, and google too when I do business with them.
Just to let you know, while you are adding to the conversation in some ways, in many ways you are distracting from it. I know you likely have good intentions, but you have pivoted completely away from the original ask and are muddying the waters of the conversation a little with the additional input in the complete opposite direction.
The twitch integration may have nice features but the OP, myself, and likely many others don't care and just want to play our game in peace without constant studio specific launchers and accounts and etc. Bringing twitch integration up makes now us focus on that as the discussion point rather than the clearly user antagonistic features such as lack of a button to skip creating an account.
I only created this after so many post of "I don't know why Larian would need to put up a launcher and ask for an account". It's to show what it actually do and why they needed it. And of course the user can just go with other higher voted comment thread. I think it is a legit reason and usage to ask you to create account and using the feature they provided, and it's also totally fine that you don't. (I didn't created an account when I was checking back and forth with Larian support about the vault account I used to use for their website. I just skip and play EA as always until like 4~5 days later a guy explained this new account situation. I created account like 1 day before launch since I want to get the twitch drop.)