Depends on your definition. They may be rare if you only include self-identified Nazis. However, if you expand that to include members of the Far Right and general White Surpemacists then they're not only not fringe but they become as mainstream as Hannity, Stephen Miller, Steve Bannon and all of the Q-anon grifters.
White supremacists -as in people who believe most of the same thing as actual literal nazis, are by no means rare these days.
But if you mean people traipsing around in black SS uniforms then sure yeah those guys are rare, sure.
The conflation of white supremacism and naziism is pretty much entirely political maneuvering. They believe very different things about the state, forms of government, gay people, culture, land use and many other things. Not to mention that only a small number of people termed white supremacists actually are (it conflates believing in racial differences (which are often not just white>everything) with believing in racial segregation with believing that the "white" ethnic group will form a better society),
Fussing about debatey details while repeatedly planting the desired concepts and trying to get anything you can, conceded so you can place a marker and push further, is very Nazi. It's foundational alt-right strategy, along the lines of 'hiding your power level'. This is not mysterious.
The reason it looks like that to you, is because fascists believe nothing… but power (and that only they should hold power, forever: it's not a thing to be shared or handed back and forth). So anything might be claimed, but outside the practical seizing of power, nothing matters.
This is VERY common. Hence people's concern about the matter.
Note that this is far from just a blue tribe thing, it's pretty universal across all politics around the world to deliberately conflate the views of your stupidest enemies and your smartest.
Also, it's still pretty fringe.
That doesn’t mean they don’t still want White America in charge; moving a group out of the bounds of the state [0] doesn’t suddenly mean there is no power dynamic, as such dynamics are evident between states.
[0] in the international sense, not in the US-domestic sense
"Just" strikes me as an inappropriate adverb to use in this context. You are talking about splitting up the US into racially segregated states. Even in a bizarre hypothetical where this was somehow done with the best of intentions (lol), the amount of chaos and human suffering it would cause is almost impossible to imagine.
This sort of utterly insane belief should not be "pretty fringe". It should be virtually non-existent, in a reasonably sane and healthy society.
It's a real sea change in our culture that racial segregation is now openly considered or even advocated on relatively mainstream forums such as HN. That some of the people in question might not meet some overly pedantic definition of 'white supremacist' is hardly any consolation.
The far right has never taken its own ideology seriously – it's all a means to an end. They tie sympathetic intellectuals up in knots trying to parse and categorize the finer gradations of racist nonsense, and then do whatever they hell they want once they're in power.
This really doesn't match my experience given how much time they spend arguing/discussing amongst themselves.
Bickering and infighting hardly constitute evidence that intellectually serious work is being done in good faith. The far right has no more use for its 'useful idiots' once it attains power than the Communist party did for its pet intellectuals.
Of course that leaves the question of how you define fascism, which is a whole 'nother can of worms.
Maximum observed 'forever' seems to be under a decade, once the full fascism kicks in and is unavoidable. I don't believe fascism is sustainable, and what we see as 'woke' is a typical reaction to these attempts at rule. (Yes, I'm suggesting that power structures lean more towards fascism than they used to, and that this creates 'woke' as a reaction to this pressure)
I'd loosely define 'Nazi' as 'fascist with specific focus on seizing power through propaganda, media, and politics, particularly with use of anything that's new media'. In the 30s and 40s, of course, this was radio. There had always been massed political rallies (though the use of epic film propaganda was also new, as there'd be no Riefenstahl without the existence of film) but there hadn't been broadcast radio. Generalized, 'Nazi' means fascism plus modern media, and I'd be comfortable focusing that down a little to specify the media's used to rally 'the people' against enemies, specifically internal enemies in an ill-defined way.
Rallying people against 'woke' through coordinated use of social media is EXACTLY Nazi, in technique.