The problem is when they ONLY thing these girls are doing is fucking sitting there and expecting money for fucking nothing, without even the decency to try and be entertaining. Because it harms the platform as a whole and makes it harder for the girls who dont want to do that shit.
I mean, they're still putting on a stream. They still have to host a stream. They still have to plan and tailor their content around the demands of an extremely competitive market. They still have to promote themselves. Furthermore, because what they're doing borders on sex work, there's also a lot of bullshit that comes with managing that that people have to be prepared for.
And i dont think just sitting there barely talking to chat or ignoring them completely while you just chill with your friends, is content.
I mean, we're getting into what I think is a more general problem with online content here, which is the relentless focus on parasociality, and if there is a risk with this kind of content that's where it comes from. Watching people you think you like chatting or hanging out can meet needs that aren't being met elsewhere in a person's life. People put on streams or youtube videos in the background just for the feeling of having someone in the room. It's not something that's exclusive to streamers who stream in hot tubs, and the very real dangers of forming those kinds of one sided parasocial relationships aren't exclusive to streamers who stream in hot tubs.
The reason being is that...again, there is no age limitation on Twitch, you can have kids fostering perv behavior because they are in some bikini girls stream while chat jerks itself off and showers bits.
There actually are age limitations on twitch. The twitch terms of service states that you have to be 13 or older, and if you're below the age of majority in your place of residence you have to be supervised by a parent or guardian. Twitch also has a setting for adult content, which users must specifically opt into seeing.
Twitch is not a particularly safe place for children. You can find people streaming R-rated games, people who use foul language or crude humour while streaming, people with unpleasant or bigoted social views using the platform to promote those views. In terms of the kinds of behaviour kids could foster on twitch, seeing women in bikinis seems a relatively small problem, and will also require that child to lie about their age.