Mostly the fact that it's become the most prominent site on the internet, to the point where its uses have gone far beyond the basic social media stuff. Just about every piece of news comes from Twitter nowadays, everything must be on there, and... well, it creates a lot of problems when it becomes that big.

Limiting every tweet to 280 characters already means it's not a good place for any kind of meaningful posts, and that's only made worse by a lot of other factors. The fact that it relies on a feed is bad enough, as that format uses an algorithm to decide on the things you're gonna be seeing, so it can and will and is used for manipulation. But then that algorithm is also made even worse by how replies to tweets are shown: the order in which they appear isn't based on how many likes a reply has, or when it was posted. It seems to be a completely arbitrary order each time, as it's also determined by an algorithm, and that algorithm prioritizes controversial responses above everything, which is why you end up with a lot of interactions like

> "I'm not the biggest fan of that game, didn't really do it for me"
> "Fuck you and your mom"

It's like... Everything is designed to cause conflict and extremism. Why? Because conflicts garner more attention, more attention means more interactions, more interactions means more activity, more activity means more ad exposure, more ad exposure means more money. It's no wonder the political state of our world has gone to shit in the way it has.

Another stupid thing that happens a lot in the age of social media is that people don't care about bringing others to justice anymore. Someone in your group said something racist? Well, block the guy and remove him from the group. Someone has been exposed as a rapist? Time to block the guy and ask Twitter to remove his account. As long as they're not on Twitter anymore, it's not a problem, right? (...) This sort of thing, cancel culture as they say, it's becoming more and more common and it's a joke. People who commit crimes should be punished under the law, not banned from Twitter.

There's more too, but anyways, you get the point. In this day and age, these things happen in every social media, that's true, but Twitter being the most prominent one means it's the one that's causing most problems, and also I believe it does it worse than most others, even if all of them are guilty of it.