Nah, most of the casuals were purged from Classic by Phase 2 permadeath, meta obsessed raiding guilds, wbuff meta, queuing against 90% premades, 99% AV loss rate/2 hour AV queues, boosting meta…
Almost everyone playing classic right now is at least semi-hardcore. Retail has way higher casual participation with achievements, mounts, pets, transmogs to collect, solo-queue BGs and arenas, LFD and LFR, and a pokemon clone embedded into the world. And in general, casuals are way less toxic than semi-hardcore players.
I do feel context is important, and if you don’t play on one of the layered realms then the experience is very different. The community in the medium realms is fairly tight, and while there is the occasional drama it really is a community.
I feel like the mega layered servers were a mistake,and they are the toxicity that players talk about in the forums. Some of the stuff that I read about in the forums would get you into a bad spot on a medium server where you do depend on the community. It doesn’t mean you need to be a saint, but it does mean there are limits to being a tool before you get banished.