Spoilers: If the avengers managed to take the infinity gauntlet off of Thanos on titan, would it have even mattered? Isn’t he still strong as hell without it and just have gotten it back one way or another?
I imagine he’d be much easier to supress. With 4 Stones, they still managed to do so, until Star Lord messed it up however. Though, we don’t know what contingency plans Thanos may have had if the Gauntlet was taken off. For all we know, he could have been using the Reality Stone to make them think they were getting it off. It’s difficult to know how much was skill, strategy or luck. Going back to the question though, I absolutley believe that the group of heroes on Titan could’ve thwarted him one way or another after a while, though I know for a fact that Thanos would put up one hell of a fight! For Thanos, it seems that it was somehow imperative that he found a way to break free from Mantis’ trance, even if it meant tipping Quill over the edge. Again, skill, strategy or luck? All of this is hypothetical anyway, because everything that happened is what the screenwriters intended. If Thanos didn’t have the Gauntlet nor the Stones, the screenwriters would have made the mad titan more powerful to be on par with the Guardians and Avengers.