“Islam isn’t a race.”
“ Muslims don’t constitute a single race.”
Yes! But it don't matter that Muslims don't actually/really constitute a race.
Leftists know that. Muslims know that. Everyone knows that.
That doesn't matter because pretending, or implying, that Muslims do indeed constitute a race works politically for both Leftists and Muslims. It has positive political, ideological and sociological results. That is, if you can hint – rarely claim outright - that being anti-Islam is racist; then you've won half the battle. And Leftists and Muslims are fighting various ideological battles.
The former Leftist battle is
to advance Marxism/Leftism/Justice/Peace by whatever means necessary
(e.g., by calling all critics of Islam "racist" and fighting racism in other ways).
The latter Muslim battle is of course to advance and/or protect Islam (e.g., by calling all critics of Islam "Islamophobes" or “racists”).
Truth doesn't come into it. Leftists admit to "lying for Justice" (a variant on the Trotskyist/Leftist "by any means necessary"). And Muslims have taqiyya (lies, dissimulation, obfuscation and distortion to defend and/or advance Islam).
American Leftists academics, lawyers, etc. are even trying to write the position
the criticism of Islam = racism
into criminal law.
So it's no longer a case of:
"Critics of Islam are racist anyway. So we may as well call all critics of Islam ‘racist’."
What we now have is the literalised:
criticism of Islam IS racism.
This is a purer form of the idea that all critics of Islam are tacit - and sometimes explicit - racists.