De-identified data is an oxymoron. Basically any dataset that's in any way interesting is identifiable.
Yes, there's a few with some quirky opinions. All of them will take money in some way.
I've never heard of that in my life
Most likely only "for". Still, a great step in the right direction.
Can I look this up somewhere?
How long does it usually take for this to make it to F-Droid?
I've heard good things about Fedora. It seems to be mostly set-it-and-forget-it while still being flexible enough for power users.