And fair enough, it's not strictly racist. I believe the semantics here don't alter the spirit of what was said (that is, discriminating against a group of people)
I'm not entirely convinced by the claim that one's religious choice being a choice means that it's not wrong to discriminate against them; what would your stance be on what the Chinese are doing to the Uighurs? (And - dare I ask - what does that then mean about your stance on the Nazi's policies?)
What the Chinese allegedly did to the Uighurs, or what the Nazis did to the Jews, is categorically wrong regardless of how it was justified; nobody has the right to sterilise or kill innocent people. But it's reasonable to argue that when a bunch of people come together to form a "country", they have a right to decide who's allowed to enter that country. Discriminating based on country of origin is not unpredecented: it's already way harder for an Indian or Chinese to get an American visa, for instance.
A religious group is not a race. When China persecuted the Falun Gong, nobody called them racist. You could say it's islamaphobic, but that connotates an irrational fear. It's not completely irrational when the values of many adherents to that religion differ so significantly from secular American values: pewresearch.org/fact-tank/2011/01/18/stoning-adulterers/.
Fundamentally the difference between a religion and a race is that race is not controllable; it's clearly wrong to discriminate against somebody for something entirely outside of their control. But people do have control over their ideology, so much as some people would advocate discriminating against racists for their racist beliefs, people can advocate for discriminating against people who believe the legal system should sentence to death adulterers, apostates (people who leave their religion) and homosexuals (https://en.wikipedia.org/wiki/Capital_punishment_for_homosex...).