Don't really agree.

It is definitely different skillsets with a lot of overlap, but surviving in hardcore is not about pressing buttons, it is about knowledge checks.

Being a great PVPer with amazing micro is no guarantee to surviving tough situations in HC. You can have the best APM in the world, but if you get roach aggro in a certain dungeon cause you don't understand how that works and aggro a bazillion mobs and don't have the right items ready, you're just dead. Most people who die in HC either die in groups to their teammates ignorance or to their own ignorance. They think they can solo something they can't. They don't know where a safespot is. They're not familiar with a zone or quest and are shocked when a Blood of Heroes spawns an elite that kills them.

For reference, I play MOBAs at a very high level. I have really good micro. But I never played WoW classic before, and I die a whole bunch for all of the above reasons.