Comment and post history is still trivial to find through a basic google query.
All that hiding them on Reddit does is pissing other users off because it breaks establish site's norms and expectations.
It’s not a bad thing. People on there, if you piss them off in a discussion, will go find your old posts and downvote them and in some rare cases harass you by replying or worse put two and two together to doxx you.
True, the only option is to not use the site entirely.