I think you are off base on this, I think there is a small contingent of the far right that are white identity adherents. The rest get labeled in with them, because they have not been vocal in their distancing themselves from that contingent, thus groups like the Proud Boys get lumped in with the white supremacist's and white identity adherents. While the Proud Boy's are a radical alt-right group, white identify is not their binding fabric. The embracing of masculinity is, they have member from all races and explicitly call out that they are not a white nationalist organization. The alt-right is a coalition, of the fringe just like the far-left. Most tolerate each other under enemy-of-my-enemy mentality.
The Proud boys do have members from all races, but not very many of them; and the vision of masculinity they present is extremely narrow rather than inclusive. There's significant internal tension within the group between the 'optical' approach espoused by its nominal president Enrique Tarrio and a more explicitly racist/neo-nazi one proposed by his informal rival, Kyle Chapman.
I think the white identity thing is more widespread on the far right than you appreciate; even neo-nazis have examples of ethnic diversity that they like to bring out (eg photographs of black soldiers in wehrmacht uniform socializing with caucasians) but these are employed mainly as an aid to entryism in breaking down reflexive hostility to national socialism, rather than because neo-Nazis are actually trying to build an ethnically diverse movement.
I am sure there is, no doubt, overlap of people that associate with the Proud Boys and also associate with white supremacist's, but they (the Proud Boys) have been very clear that white nationalism / supremacy is not their charter and I do not think it is fair to paint them with that brush. That being said, I do agree with you on their view of masculinity and it is fair fodder to critique them on. That is their point, they stand for a certain set of values, they are very clear in what those values are and that is what they should be weighed in the balance for. For the record I am not defending them, rather I prefer to see peoples arguments weighed for what they are saying not for what other people paint on them. It's not fair and it is attempt to dilute their message. I think their message stands for itself and most people will reject it. Attempts to paint them as a racist organization when they are clearly not, only muddy the water and lend credence to their argument that they are being treated unfairly. It plays into their hands.
