First of all "everything Spencer says is basically left liberalism" is a gross misrepresentation of his views.
The bigger issue is just a difference between American politics and European politics (one could include Israel as well). Spencer's views fit very well into what Israeli right wing or European right wing parties want, while they might not fit in with the Republican party very well. I don't really have a problem with this, because I dislike Republicans at least as much as Democrats, but I understand why it causes confusion.
For example, "conservatives" fully support the national health care systems of Europe. These are seen as benefits for the European people, and just as the Belgian police should help any Belgian who is the victim of a crime, Belgian doctors should also treat any Belgian who is sick. That is a basic tenet of their society. Whereas in America you have a weird mix of all kinds of different races and classes, and people often do not want the state to help those from the classes they don't belong to.
Likewise, European politicians from both sides are far more aware of Jewish influence, and indeed there is often criticism of Israel from both sides, whereas American Conservatards in particular (but really also libtards) will think you're evil if you criticize Israel.
The American Right is one of the only political parties that (pretends to) believe in small government. Conservative parties throughout Europe don't want government smaller, as much as they want it to do different things than European leftists do.
As for the vaccine issue, I'm still wary of the jab (or at least the Pfizer and Moderna jabs) but in a homogeneous society like Europe or Israel, it is far less likely that the nation is harming its own people with faulty health care. I'm coming around to the idea that the vaccination stuff is really just prepping us for a control grid. A vaccine mandate is less about making sure everyone gets a shot than it is that everyone is tracked through apps and their purchases are monitored and can be switched on and off.
I think he is rightly criticized for certain views, but at least he does hold these views, whereas I couldn't begin to tell you what the Republican party actually believes in (other than wars for democracy, nominally states rights, and funding government indirectly through inflation rather than directly through taxation).