My only issue is having WhatsApp in my circle is a must.
Friends and families are more than happy to text or call. But the numerous contractors and engineers I work with and request their service, to them WhatsApp is a must to send photos of issues or videos of faults.
I think one that can be done is to create a pinned FAQ post in Reddit on the fediverse sub Reddit. I have seen so many questions popping up lately with a lot of potential users that seem confused.
I know Samsung phones can do something similar with a built in Modes and Routines feature. They allow you to access things that otherwise would require root from tasker.
Even though the android version of it has been discontinued, Syncthing remains my top FOSS app. Not sure how it will behave in the future but v1.28.1 works well for now.
My advice would be to look into emulators. Old school games do not have any micro transactions and are complete. Plus there is a vast library of consoles and games to go through.
If it's open source and can be hosted locally, I don't think there are issues with national security in this case.
There is money to be lost though. Always follow the money.