Rif has a feature where you can filter out posts which links to a specific domain (regex like syntax).
For example you can block all posts which redirect to youtube.com or youtu.be.
Couldn't find such feature right now, but would love to see this.
I hate clicking on youtube posts, I don't watch content with sound, and it also opens the youtube android app with ads and everything.
This could be extended to a feature to filter out posts from specific instances till its not implemented in the backend.
These could be done on the frontend like after the client recieved the posts to display it filters them by domain / instance by user defined rules