People aren't necessarily going to "say" something just because a man took off his shirt, regardless of their opinion of the quality of the view or whether it comports with park rules. We see topless men at every WDW pool and waterpark, reflecting every possible level of objective beauty, so most of us are immune to the hairy backs, questionable moles, topographic stretchmark maps, regrettable tattoos, jiggling Santa bellies, fluffy moobs and plate-sized purple nipplage that tend to dominate the territory. If you feel it necessary to expose your share of that glory (your "Lands of Wonder," if you will) with the good people on Splash Mountain and moreover to post about it here, however, my guess is that whether others "say anything" to you, or whether they're bothered at all, is not something about which you care.
That being said, the rest of us tend to keep our clothes on when we experience WDW attractions...