I treat it like Yelp.

Most people who use Yelp are there to be Karen's and whine about things. But enough people are whining about the same thing, it's up to you to verify during the interview. And HR at the companies I worked at definitely look at Glassdoor reviews for feedback.

For example: I don't like working more than 40 hours and I especially don't want anybody to call me on the phone. It's a non-negotiable.

If I notice that in glass door reviews, I bring it up. Maybe that phone policy was for another dept. Or it was a shithead manager who got canned.