Maybe our company was just unlucky with the sales rep assigned to our profile, but altering reviews was something they made clear would not happen regardless of if we paid or not.
At the time our company was getting negative reviews meant for a different company in a different country with a similar name. It was a major hassle to convince Glassdoor the bad reviews weren’t legitimate. Eventually they were removed but it required a lot of persistence emailing / calling them every week and providing evidence the reviewers never worked for our company. Meanwhile we were stringing their sales person along hoping that would make it easier, but I don’t think our sales rep had any sway.
I dislike Glassdoor especially for small companies where 1 unhappy person on a team of 15 can ruin their employers reputation from the perspective of future hires. IMO they shouldn’t allow reviews on public company profiles until there is a critical mass of reviews such that any 1 review won’t dramatically swing the star rating.