As for the fake reviews… People across the org may have wildly divergent experiences working at a company. Even a fairly small company. Often the person who someone reports directly to has an outsized impact on said person's experience. In an early stage company the individuals doing people management tend to be, at best, very new to that specific part of the job. At worst the company grows large-ish before any official "reports-to" structure is put in place.
I've worked at places where my advice to leadership would be "keep doing what you're doing" while other Glassdoor reviews seemed to have had one of the worst experiences of their lives. That doesn't mean that I planted a review. Maybe I had a particularly good manager? I could have worked in the only good part of the org or a negative review may have come from someone who worked in the only bad part of the org.
It's pretty easy to openly communicate with management (all the way up to c-level) in my experience, no need to put it on some website when you could discuss it with them directly.
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