Islam isn’t a race.
Muslims don’t constitute a single race.
Yes. Though it doesn't matter that Muslims don't actually constitute a single 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 and ideological results. That is, if you can hint – or claim outright - that being against 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/"social justice" by whatever means necessary.
The latter Muslim battle is of course to advance and or protect Islam.
Truth doesn't come into it. Leftists admit to "lying for Justice" (a variant on the Trotskyist/Malcolm X/Sartre "by any means necessary" mantra). 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.