My PC is hinting at me to remove "Flash".
Does it do anything anymore?
Safe to dump it without breaking any other program?

It's going to be fully deactivated in January, IIRC. RSN, one way or another. Some things might not work, but then you complain at them for being laggards.

I know of nothing flash anymore.

I haven't had any form of Flash enabled on any of my devices since Chrome shipped it disabled by default in version 76 (July 2019) and haven't noticed it. My son's online high school learning system still relies on it though, so your experience may differ from mine if you rely on a site that relies on it.

If you can disable it rather than remove it, that may be a better way to go.