You can sort of block publishers/devs, if they have their own “steam page.” If you click on the publisher/dev in the listings underneath review scores, if it takes you to an actual dedicated page you can click the gear icon on the right and click “ignore this creator.”
This does not completely block them but it has them show up in less places (or are greyed out in some places.) Basically they can pop kinda randomly up in sales when steam forgets to add that, or greyed out in the tabs section on the front page (new and trending, top sellers, popular upcoming tabs)
It’s not the cure-all “erase EA” button I’m sure we’d all prefer, but it does help a little.
Freetube instead of youtube, Thunderbird calendar instead of something like google calendar, Signal instead of Discord or text, Tellico for all media lists instead of something like goodreads or online movie or game lists, Obsidian or Joplin for notes and organizing creative pursuits