I will not buy or even watch any videos which include prolapse or pissing. I don't even know how it is legal on camera haha. However I guess everyone has its own preference. No performers are forced to do anything. I think these are such things that even if they been offered with an extra 100, 200 or 400 usd they would still say no to if they are absolutely not comfortable. No is no. The moment a studio would force a girl to do something they don't want would be consider serious sexual harassment and could make any studio close or in worst case owners to jail. (Just look at that Max Hardcore clown, I hope he gets dry BBC QAP every day from his cellmates.) Even if the studios been managed by some evil assholes (they don't

) they still wouldn't force anyone out of fear of lawsuit&reputation.
Another question is supply and demand.
Supply wise - you can always find models who want to experience crazy crazy stuff while in this industry, takes the whole stuff as a well paid adventure, and will do [triple penetration while two dicks in her mouth and jerking 2 more while 4 more guys cuming to her hair] or whatever needed. Finding models, even beautiful models won't be a problem and it will even be easier in the future.
Demand wise - I personally understand what you want, but I would say unfortunately there is a tendency in porn audience that the more years u spend by watching porn the likelihood that eventually you wanna see something more extreme raises. I for example started just playboy like naked pictures, then solo masturbation, lesbian then POV, then POV but like a threesome, foursome, then orgies, then hardore orgies like Outnumbered and after I also started to like gangbangs and then more crazier ones Now, I got to a point where I would also enjoy the mad example I wrote to you haha
So more and more people wants to watch crazier and crazier stuff and there are more and more models for it.
I think the solution is separation.
Let me explain what I mean:
There could be commonly accepted 'levels' of porn. Such as Lighter/Softer, Normal, Extreme, and Bizarre and these combinations under a Mixed category. And they wouldn't be treated the same way.
This separation is important for Tube sites mainly. Like if I will have a kid, I want her/him to feel free to watch porn when gets to legal age, I want sites where there are no videos where they pour cola to asshole and shit like that. And I don't even want her/him to find such on the tube sites. And I don't even want them to - by a long journey of clicking here and there, they could be leaded to such videos.
Extreme and Bizarre should be provided by niche sites. I wouldn't even mind if, - tho possible, but wouldn't be so easy to find these niche sites.
And on niche sites like this Legalporno, they need to do a better job separating stuff. I for example okay with TP but I am disgusted by pissing and prolapse. I would love to be able to use Legalporno without ever seeing any of those. Like for example there is a Hungarian-Cocos Islandic torrent site, where I can choose/checkmark that I don't want to see a certain category of torrents ever and then I wont.
This would stop/slow down the journey of people going from Soft to Extreme and you would also just be able to see what you want.
And again don't worry there will be plenty of good looking models in Legalporno, I'm sure about that.
A last aspect is that no harmful and painful stuff should ever happen in these videos. Of course pain is relative when we talk about anal sex, but if there is a dap or even tap, the pain should be relatively bearable and for some crazy performers 'doable' or even maybe for some crazy extned 'enjoyable' same with kinky stuff. But the moment I would see someone having significant pain/getting harmed, I would report the studio and never ever watch it again.
Sorry for the damn long message, but I'm high a bit, so I just went full blown
analyses mode haha