which is the point. Ignore means you can't see them. it doesn't mean they cease to exist on the forum. They haven't chosen to have any functionality removed for themselves and really, if you're ignoring them, why care what they see or respond to? you're never going to see their response anyway. I looked, I do have a couple people on ignore, some aren't even here anymore. I forgot they were even there. No clue how many times they've responded to me and don't care. Should have been a quick conversation for them when nobody replied.
Ignore causes some functionality issues like blocking entire threads started by an ignored person even if 90% of the content is from people you want to read stuff from. I don't see any need to introduce new stuff that will then limit functionality for people that aren't choosing to have it limited. just use ignore like a true ignore. If someone says something to me, I won't know and if I've already determined I don't care what they have to say, why would I care?