I'm not sure they would help a lot to be completely honest. Any service committing to this whole 'taint' thing would for one, heavily resist such a change to Bitcoin and maybe even try to fork it or some shenanigans like that (of course, not before spreading enormous FUD about the proposal and telling everyone that it's initiated by criminals, to protect other criminals).
Let them try. You would either end up with a small number of centralized exchanges forking to some niche altcoin which would quickly die (and those exchanges along with it), or if you somehow reached consensus among a majority of large exchanges for a fork (which would be near impossible since they would all want to somehow exert majority control), then you would be left with essentially a CBDC.
Do the people who currently use Bitcoin with 0 privacy (who would gain some by this procedure), deserve it?
Do people who use inappropriately high fees deserve segwit? Do people who use inappropriately low fees deserve RBF? Shouldn't they all just learn to look at the mempool rather than have us implement time consuming protocol changes? Changes are driven by what is good for bitcoin, not by what its users deserve.
Do you believe this is because of ignorance, brain-washing or maybe it's much more complicated than that?
Bit of all three. Modern life is filled with indoctrination that you don't need any privacy, or that giving it up is a good thing. Go to social media and broadcast your entire life to everyone. Sign up for an account and receive $5 off your next order. Let us track your activity for more personalized results. Let us record everything that happens inside your own home so you can turn off your lights with your voice.