Doom was popular on the SNES and it was even ported to several other home consoles.
The only reason the design was different between PC and consoles at that time is because PC was way more powerful than home consoles. You could do stuff that the home consoles couldn't do. This changed in the 2000s because home consoles started to get much more powerful and it has reached a point that home consoles are similar to high end PCs. What you can do in PC you can now easily do on home consoles.
This had nothing to do with mainstream and it was just an hardware limitation gap.
It wasn't just the hardware, but the input methods and player base. PC users weren't limited to a small controller with few inputs, and were more likely to be used to complicated interfaces. Just getting a game running on computer could be a chore compared to plugging a cartridge into a Nintendo. Plus the massive price difference.
But the reason for the gap is irrelevant to my point. The gap existed. Complex RPGs, strategy games, obtuse adventure titles, etc ruled PC gaming; while consoles were doing what made sense for the control inputs and data storage limitations: platformers, racing games, etc. Ports of the most popular PC games were still ports. They weren't the most popular titles on those consoles (and for good reason, as they generally did not play as well).
Once the design gap closed and release parity was more common after the turn of the century, it meant that PC releases would be more likely influenced by design decisions that made sense for a console audience and hardware.
That is my only point. I am not trying to say anything about grouping people into hardcores vs. plebs or anything like that. Console designs influence PC designs. And the movement of RPGs away from isometric perspectives or stat heavy interfaces is an obvious part of that. (Also see just about any change to the FPS formula in the past 15 years: checkpoints instead of manual saves, weapon selection wheels, only carrying 2 weapons at a time, iron sights to compensate for thumbstick inaccuracy, etc).