I play on PC with a controller, that said my MMO experience is FFXI and FFXIV (played a bit of 1.X, been playing 2.0 to now), which both have controller support. And I started ARR on PS3 since my PC at the time could barely run it at minimum (also is the reason why I only played a bit of 1.X lol, was basically unplayable on the hardware I had).

I've tried to learn KB/M a few times over the past few years, but I could never find a keybind setup I can get used to and stick with. Using the number row with CTRL/ALT/SHIFT for skills feels unnatural to me, and rebinding to other keys started to confuse me in practice xD