why?

It exemplifies and exacerbates all the worst aspects of the internet: clickbaiting, irrelevant oversharing, uninformed commentary, reactionary groupthink, mob harassment, inaccurate and deliberately misleading news, etc.

What positive value does it provide in your opinion?

Instant reports of witnesses about ongoing events and instant statements from those who are supposed to be in control of the ongoing events.

It's invaluable.

It's the only generic, centralized, realtime source of news. The key is that the definition of "news" is quite broad.