Popular: 5e. The design intent was for the masses after all.

Influential: 3.5e. Warlocks, modern kobolds, reasonable Psionics rules, complex martial characters, Dragonborn, and above all that and more the OGL content. As mentioned up thread PF1e was a long running reminder of the system’s impact. I will also blame (credit) 3.5e for the general rejection of “lots of fiddly numbers” in TTRPGs as it rose to be the main antagonist in such discussions.