All we're telling you is that, as those who've indeed been told that for so long, those words are dead to us.
And I'd add they're word salad to the other side when used generically in a political campaign, with about as much semantic meaningless as Blue or Green in pre-Nika riot Constantinople.
Shades of Bill Maher saying, sorry about crying wolf over our telling you the Current Year Republican presidential candidate was Literally Hitler (although he should have gone all the way back to the first example in 1948), this time we really mean it.
Circling back to your desire to re-imbue meaning to them, I don't think you'll see that in your lifetime. See, for example, the hundred year cycle of progressive -> liberal -> getting back to but not quite there yet progressive. When words and the concepts behind them get burned like this, it's really hard to recover.
And, yeah, it's much worse than the surface which we've mostly been discussing this at, the very concepts have been rendered stone cold dead.
Maybe it will indeed be really hard to recover. Then again, my determination just got reinforced.
Did I engage in introspection the first time I was called racist in this context? Yes, of course. 10th time? I don't think so.
The danger here, of course, is that having stopped outside sparked introspection after the message became perceived as a "Nobody likes me, everybody hates me, I think I'll go eat worms!" one, I of course may have drifted into it.
Almost certainly a bigger factor in the US is that this has been used to divide us for political gain, and now that we've become an polity where identity rules, it's anti-survival to continue to play by the old no longer operative rules. For a degree of automatic discrimination against other identities who are in direct, existential competition with me as a white, heterosexual male is a requirement if I want me and mine to survive the next few decades.
Call it racism (except, of course, We Don't Care), call it realism, those facts on the ground have to changed before movement towards your ideals can be realized in the US.