Yes. It's like a pseudo-union. Collectively bad companies are avoided and good ones receive more interest. Low salaries and bad managers are put on display. Good ones are, too.
It's useful for the job seeker, and it's useful for society.
You're saying it is corruptible. But it doesn't have to be perfect to be useful. There's plenty of critical reviews on the platform. More than enough to take a peek into the problems some corps have before joining.
No. I've looked up companies that were great or awful, and the reviews looked about the same. A fee negative reviews from the janitor, and lots of positive reviews that look like they were written by the PR team.
