Like the editors of National Review and the Proud Boys are in loose coalition.
This is a really good example that should help you better understand how analogies and connections between things work. When people draw an analogy between X and Y, they're saying that X and Y are similar in some relevant way. They're pretty much never saying that X and Y are similar in
every relevant way, because if they were then X and Y would be the same thing and we wouldn't distinguish between "X" and "Y" in the first place. That's why it's bad to talk about analogies as if you're "conflating" two things or "drawing an equivalence" between two things. That's not really what analogies are. An analogy is not an equivalency. It's just an observation that X and Y are similar in some particular dimension while still acknowledging that they may be very different in other dimensions.
National Review and the Proud Boys are similar in that they are both part of the American right. Nobody can really deny this. Everybody at NR would comfortably place themselves somewhere on the right hand side of the political spectrum. I assume the Proud Boys would as well. (I don't actually know much about the Proud Boys -- I'm going on my general impression). If somebody wanted to talk about right-wing schools of thought and they drew a connection or made an analogy between NR and the Proud Boys for that purpose, that would be totally fine and accurate.
NR and the Proud Boys are different in that one opposes violence and the other advocates for it. (Again, that's my understanding of the Proud Boys -- indulge me for the sake of argument). If a person were to draw an analogy between these two groups to argue that all right-wingers love violence or hate violence, it would be a pretty terrible analogy because these two groups, while similar in
some ways, aren't similar at all in
that way.
The capitol hill insurrection and the George Floyd riots were different in lots of ways. The average daytime high during the 1/6 riot was way lower than the average daytime high during the George Floyd riots. The 1/6 riot was localized to one fairly specific location, whereas the summer riots were nationwide. The 1/6 riot caused relatively little property damage compared the summer riots, and there was quite a bit less loss of life. The 1/6 riot directly involved the seat of government and threatened people in the line of presidential succession, but the summer riots didn't. The 1/6 riot was right-wing and the summer riots were left-wing. Lots of differences. Nobody thinks that these two events were exactly the same.
What the summer riots and the 1/6 riot have in common is that they were both politically-inspired acts of violence. Lots of us think that politically-inspired acts of violence are bad*. That's why we connect them. The summer riots were bad. CHAZ was bad. The 1/6 riot was bad. It's very easy to condemn both when you're not part of a tribe.
* Yes, yes, I know: but what about baby Hitler and my time machine? That's not what we're talking about here.