Is privacy still worth pursuing?

;TLDR: Is privacy actions on an individual level worth pursuing, when friends and family are doing nothing to strengthen their privacy and when living in a country where my social security number, phone number, and so on, really can not be hidden?

Hi fellow DeGooglers. I have spent the last few years degoogling mine, and my GF:s lives and I am really happy about coming as far as I/we have come.

I am now starting to doubt alot of the things we have degoogled in our lives and I want to ask this community about it.

We live in a country, that has national records about everyone living in the nation. Almost every service the inhabitants of this country use, are relying on social security numbers, phone numbers, email and so on. We also almost daily rely on our banking apps to identify ourselves when using different services.

To this day I have persuaded a lot of our friends to use Signal but all of them use Signal as an extra app to communicate with just me or my GF.

My GF still has Instagram/Snapchat/Facebook, you name it and I am wondering how private I/we really am/are when the friends I/we are interacting with, are doing nothing to strengthen their privacy?

Is I wrote above, it is common for me to give my address, phone number, (throwaway)email when signing up for almost any service in the country I live in. Oftentimes one also has to identify with a form of a banking app, that almost all residents in this country has.

I am thinking that alot of the services I, have to, use know who I am, they have my phone number and they are almost certainly sharing it with third party companies (within GDPR). These companies also have the phone numbers of my friends who have my telephone number, and that way, the big data companies could easily link my phone number to who I am, based on that my friends and family have my number in their contacts list.

Is privacy worth pursuing on my part, or is it actually just redundant? Could I actually just use, lets say, Whatsapp/Messenger/Snapchat and it would not really matter?

Edit1: Services that I use: Proton, Mullvad, GrapheneOS, Simplelogin, Nextcloud, and all the usual FOSS apps everyone is using Services that my GF uses: The same as me, but also Instagram, Snapchat, Facebook, Messenger and a few more.