While your concern is valid, it is instance specific. They can turn their whole instance paid, make it pay per message. The point of federation and an open standard is exactly that the user doesn’t have to give a f. matrix.org is not the only homeserver and user has the power to make their own homeserver as well.

There’s a separate f-droid archive repo. By adding the repo older version of the apps can be accessed

Ok for me If it’s media size related. As storing media requires more storage than text.