I'm actually fine with settings toned down to almost nothing, but the one single thing that I'll never crank down if I can is the texture quality and character draw distance. I don't like looking at blurry smudges and seeing nothing...
Ya know I grew up with vague memories of my mom's 2600 and I had an NES in grade school. So I've dealt with marginal graphics over the years and I can handle anything worth playing as long as 20+ fps (years of shatty computers have also helped). So as long as the core game is fun, yeah I can play it just about any way/any setting.
But you do make a good point about draw distance, I don't mind per se but games these days kind of count on a certain amount of view for the PC and that can really just break even a fun game.