There's a key point here. The browsers are becoming things that a lot of users don't want.

There are different audiences. The audiences that are prepared to spend some effort need ways to get what they want.

(Not the average result of an unrepresentative focus group, or however these things are designed.)

Do we need a browser toolkit, that we program ourselves? Do we need better customisation?

For RSS I have used FeedDemon for years. (The in browser implementations have always sucked for me.)

If Facebook won't give me decent RSS, then I can't use it much!