Who are your "must follows" on Mastodon?

I have no explicit suggestions but I will just repeat what was told to me: hashtags are your friend. Find people associated with those that interest you.
Actually I take that back, the one suggestion I do have is Low Quality Facts. Their posts make me snicker usually.
- Get ready to block a lot of spam accounts if you follow hashtags though
  
  I haven't really had this problem and I follow a ton of hashtags. Also it's good to report spammers so that their server can get rid of them.

Definitely Taylor Lorenz. She’s almost always on trending, but she’s a journalist always posting about twitter and musk’s controversies, very interesting content.
We Distribute is kind of like a publication about the fediverse. Great content.
Linus Torvalds. This one’s pretty obvious.
But I’m still looking too! If you’re into tech, you will almost definitely find something for you on mastodon, especially free software. Good luck!

@feditips@mstdn.social is a must follow for me.
Beyond that let finding people happen organically. Focus on finding hastags and groups to follow, then the interesting people will start to bubble up in your feed naturally. See also.
And if you're on a niche/topical server don't forget to get an eye on your local feed. It gets swamped on big instances but can be a great discovery tool on smaller ones.

I don't have anything to share really but I'm here for the suggestions and making a comment to come back to later while increasing post engagement lol
- I too am increasing engagement!

@ZachWeinersmith@mastodon.social is the author of the SMBC webcomic and he posts funny stuff pretty frequently.
@davidrevoy@framapiaf.org does art with open source tools, including the open source Pepper and Carrot comic.
@SmudgeTheInsultCat@mas.to posts dumb memes constantly.
@Popehat@mastodon.social posts smartassed yet accurate commentary on current legal news.

Wait until Friday and check out the #FollowFriday hashtag... this guy is pretty lame though.

This fella called DJDarren. He's brilliant. https://mendeddrum.org/@DJDarren
I heartily recommend Fox News*, but otherwise I'd suggest looking up hashtags of things you're into and following people who like what you like. And follow other people on your own server too.
It's kinda tricky, because most of the people I follow might not be interesting to others, but they're mostly good for chatting with.
*please click the link before attacking me...

I don't complicate my life with lists 1 Someone follow me 2 Lookin in the profile which themes he has 3 If it interests me, I follow back, if not, well, not.