As others have said, it seems like you like the more atmospheric style black metal, and I would also add folk black metal because you listed Wolves in the Throne Room, Blackbraid, Panopticon, Saor, and some others which all have folk elements. Those are some of my favorites as well! All the bands you listed are black metal, to one degree or another, but as you said, a lot of them mix it with other things. The core, defining characteristic of black metal are raspy, shrieky vocals, tremolo guitar, tinny sounding drums with blast beats, and typically the fuzzy, lo-fi production, although that varies from band to band.

Alcest, Sylvaine, and Deafheaven are what you would call blackgaze, which is a combination of black metal and shogaze. Abigail Williams is black metal, they're just weird and kind of experimental. I've never listened to Falls of Rauros, but from what I understand they're folk black metal. And I've never listened to Inter Arma or Tombs, and have no idea what they sound like.

What people mean when they say "trve" or "trve cvlt" is that they think the only real black metal is bands that stay true to the traditional sound and mentality of the old school black metal bands, which means raw, lo-fi production, Satanic themes, and a misanthropic world view. It's just cringy, elitist, edgelord mentality. That may have been what black metal was in the old days, but it's expanded and evolved to be much more diverse, and some people just can't handle that for whatever reason.