At the very end of the Gauntlet of Shar there is a pop up warning you that progressing further will cause you to be unable to complete certain quests but it doesn't say which ones. I assumed they were referring to side quests, not everything in Moonrise Towers besides the boss fight. As a player, because those quests were in the same area as the boss, I assumed they were to be done as part of the final assault in the act and wouldn't be something that would get locked out from what appeared to be just a companion quest. When you find the Gauntlet of Shar on your own, it makes sense to go ahead and do it because of Raphael and Shadowheart's quests. There is nothing there that indicates you are doing something that will lead to the end of the act until
you come across the Nightsong
at the very end.
I think it would be really helpful to explain to players just what they will be locking out. Maybe have the pop up straight up list the quests in their journal that will auto-complete? Or have a companion remark that
those tieflings need to be saved ASAP
like what was done with Nere?
In all honesty, the amount of content this lock you out from makes it feel like it was never intended for players to stumble upon the Gauntlet without reading about it in Balthazar's room first. I feel like I missed out on half the quests in this act. And if that's the case, I'd even be ok with a little railroading preventing players from even entering the Gauntlet before going to Moonrise first. The player experience would be better in the end, in my opinion at least.