Streaming has had visual donations for a long time. It is a form of donation, when you can send a message for an arbitrary payment, which will be displayed on the stream.
If a streamer has no big viewer base - it’s completely OK. Less popular streamers, in average, have better behaved audience (my personal observation, not backed by statistics). For bigger hosts - the ability of any viewer to affect the stream’s video/audio output leads to a complete disaster. It immediatelly becomes so polluted with noise, misleading information and toxic behaviour. People just want to get their piece of attention all the time.
I, personally, watch broadcasts only because of the host/hosts way of putting it together. Only thing that attract me - is how the streamer plays, talks, thinks. I don’t care about big interaction with the viewer base. I absolutely don’t care about viewer’s messages, except, maybe, a streamer reading the questions of his/her choice from the chat. This way it feels like a broadcast with a structure. Otherwise it is a common room where everyone can throw out their opinion, interrupting and don’t give a fuck about each other.
And now we move on to the biggest drawback of the recent streaming culture. The hardest blow on broadcasting quality - memealerts. They are small pieces of video material, with sound, which appear at the random place of the broadcast’s view.
Memealerts can be send by any user for a, defined by broadcaster, donation. They can overlap each other, mixing also in audio output.
One beautiful evening, i went to a GTA IV stream, to watch how one of my favourite broadcaster plays, and saw this:

And this:

Cool to see the gameplay, huh? 30-minute stream of such a noise may lead to a serious brain injury.
The initial hype of memealerts for certain streamers was big - some of them received thousands of them per broadcast day. For me - this completely invalidated watching certain streams for a long time.
These days i’m very happy to see many streamers, that i liked to watch, started to either turn off this feature or increase alert’s price.
I’ve seen some russian-speaking streamers to talk about their “heavy brain” effect after ending the translation, for example, melharucos (but, unfortunately, i don’t have a certain reference). Such an effect is without a doubt is caused by a heavy load of information coming in. If we don’t analyze and “digest” the information - it leaves as a burden in our neural connections. Symptoms of “heavy brain” i’ve experienced myself:
I completely understand why many streamers i loved turned on donations, then memealerts. The reason is not only money, but, maybe, such features were considered as broadcasting “support”. But once you got into that noise hole, it’s hard to get out. Constant information input is fastly killing an ability to think.
Information-consumerism culture is crawling in all spheres, people just can’t live without new piece of content, the action must go on, something should happen on the screen all the time. No minute of silence should be spent.
Such a noise kills our ability to think by ourselves. Instead we start picking up someone’s else ideas, that we haven’t even tried in practice, and putting them up as our own. You cannot excel at anything if only thing you do is consuming.
Moreover - such an intensive amount of garbage information, which i believe memealerts are, can lead to a serious cases of burnout.
I’m very picky about broadcasts to watch. When i go to the streaming platform, i most probably know which content i want to see there. I rarely wander around wasting time. For example, i go to twitch in the Monday’s evening, want to see some Dota 2 content, preferably pro-play, without toxicity. Since it’s evening in my timezone, i know that it is probably, Dendi, DreadzTV. If no options are available, i simply close the site and go rest. Prefer rest over consuming.
Streamers i loved, but who stepped onto the “noise” path, are, unfortunately, no more on my list.