I'm disinclined to purchase a game with a strong agenda, assuming of course that I disagree with that agenda. Often, I find the agendas in RPGs more laughable than offensive, but neither reaction inspires me to pick up the product.
If a game trumpets an agenda that I find not just absurd but downright revolting, I wouldn't buy it even if it had mechanics I'd want to crib. Most such games tend to be lame across the board, though - the previously mentioned Nazi game comes to mind.
Offhand, I can't think of a game with a strong agenda I actually
agreed with, so I couldn't tell you how I would react to that.
The central point, though, is that I'm very strongly disinclined to
GM a setting if its agenda is basically the whole point.
I never ran Dark Sun, but it had enough variety and interesting material to cover without buying in to the metaplot's themes. If I'd gotten a group together for Dark Sun, it would have been morally ambiguous sword and sorcery, not superficially gritty eco-fable.
I would have then, and would today, enjoy running a morally ambiguous sword and sorcery tale set on Athas. That tale would involve the setting, with its defiling wizards and corrupt templars (though I would probably drop the preservers) but it would simply accept their existence. The templars run the cities, magic takes its toll - what of it? "Athas?" If something as big as a planet can't take care of itself, what do you care? You care about your own sand-blasted mercenary hide and you draw steel (if you can get it) and psionics to protect same!
If the agenda is so ingrained in the setting, and the setting so otherwise bereft of interest, that I couldn't run a game set there without stripping all thematic elements from the adventure, I would have no interest in it. Dark Sun makes for a very cool post-apocalyptic fantasy world without environmentalism being central to the metaplot. Many agenda-based settings do not.
So, in the case of the euphemistic "Tolerance for Oozes," it would boil down to two things:
1. Do I find tolerance for oozes a laughable, overrated, shortsighted or otherwise bad idea (if not downright offensive - for example, if dwarves, my favorite standard fantasy race, are depicted as being cruelly, exceptionally intolerant to oozes)?
2. Is there enough to the setting that I would have reason to run a campaign there, or at least have a spelljamming shipload of PCs pay it a visit, with tolerance for oozes essentially excised from the material?