Suppose the idea of fundamentally evil humanoids is indeed removed from D&D entirely, because of its problematic aspects. There are also many monsters in the other creature types that resemble humanoids. Undead and fiends have already been brought up, but I think we can all agree that there's room for those to remain inherently evil. (Ditto celestials being inherently good.) You could also argue that constructs, as artificial creatures, could also have inherent alignment (though they're usually unaligned anyway).
But what about giants, which are basically just big humanoids? Monstrosities, like ettercaps? Fey, like hags? Aberrations, like mind flayers? Elementals, like efreet? Plants, like blights?
And that's just limiting examples to creatures with humanoid shapes, there are plenty of other intelligent creatures in those types. Plus dragons are certainly intelligent creatures... and currently color-coded for alignment convenience. There have historically been intelligent oozes, even.
(I guess beasts are sufficiently inhuman and unintelligent by default to never be a problem, but they tend to be unaligned.)
The question here being, if inherently evil humanoids are a problem - and I acknowledge folks have authentic concerns here - what happens if folks just replace "orc" with "ogre" as their go-to "kill without remorse" monster? Or ettercaps or hags? Is that still a problem? Is there a line beyond which they're inhuman enough it's acceptable? If not, how far would we have to go to actually address the problem at the default level?
Note, BTW, that we already do have playable monstrosities (centaurs and minotaurs) and fey (satyrs), thanks to Theros. (The Theros minotaur is implicitly humanoid, admittedly, but the Theros centaur is still not a humanoid - they're fey.) And per the recent UA, we may have playable constructs and undead on the way as well. So arguing that just "humanoids" should never have fixed alignments won't work, that ship has sailed.