Both ran well enough to run wordperfect on a 286 with 1 meg of ram. OS/2 wouldn't even boot under 4 megabytes of ram, or with a 286 processor.
So yes, vastly more expensive hardware requirements is certainly a valid criticism. In 1992 nobody had 386 machines. Some even say IBM purposefully designed it like that, to sell more machines. But if they did indeed intend that, why not release the OS for free ?
In 1992? I think this was after for example the infamous AMD 386DX-40 was released. Granted there probably still were a lot of 286s out there back then of course, which is one of the reasons why I never suggested abandoning DOS/Win3.x immediately. Of course, as mentioned before this would cause some pain for application developers, but this would last only a few years, and even PX00307 mentioned "Porthole" (aka WLO).
By 1992, 386 machines were common, and new machines for serious work were generally 486s.