Twitter is definitely not just a link middle man, the main use for most is to follow people that use Twitter as their main way to talk/make annoucements about what they do. Be it politicians, artists, event organizers, teams, players etc.
For example where I regularly see links to Twitter is when people/organizations announce what they’re doing with eSports tournaments. They don’t announce that anywhere else. So if you want to be informed at all, you must have someone viewing their Twitter feed, either yourself or through someone else.