Quit making useless changes. If it ain't broke, don't "fix" it.
Is Yahoo mail trying to go out of business If so, tell the users. If not, revert. Allow ad blockers. Support Yahoo Groups again. Don't take away forwarding. Yahoo personnel should questions directly. Give me a phone number to call when I have a question. In summary, look back at what Yahoo mail was 3 years ago and go back to that time with those features.
Lawrence McGuire commented
BINGO!!! RIGHT-ON TARGET. DON'T DRIVE USERS AWAY.