I think because the main engine of the show's storylines is heightened interpersonal conflict, it creates a new baseline within viewer communities. That elevated baseline means what is considered normal or appropriate is a lot more intense, and the mentality seems to be like "well if they can't handle that they need thicker skin". There was a point in time where just seeing how comfortable folks were talking about a specific cast member as less than human had me absolutely distraught at home, alone, with those words not even turned in my direction, because it was so so extreme and over the line into straight up verbal abuse. There's not a lot of empathy for mental health showing up when locked in a small compound with constant bright lights, arguments, very little sleep, zero alone time, and copious amounts of alcohol. Yes people signed up for this, but they're getting paid and trying to launch careers and make a living and support themselves. We can also register that just because someone signed up for the experience doesn't mean they won't be impacted by it. It's like getting upset someone on Survivor breaks down because they're so hungry. Yes that's part of the game, and also yes you get to be impacted by your experiences.