Glassdoor is not reliable. Companies can pay to suppress negative comments.
Are there trusted impartial review sites?
They exist, but are very few - their articles get stolen by unscrupulous copycats, or the AI slop buries them in noise. It’s like panning for gold, but instead of a bubbling creek it’s sewage runoff. I hardly ever find trustworthy results on the first page any more, you got to go several pages deep until you stop seeing the “Top N <search term> you absolutely need to buy!” results.
I’ll make one exception for audio messages: the other person being in a situation where they cannot easily type the message, but it’s not an emergency. Hands full, driving, inclement weather, etc. I take it as an implicit “this message is important, but not drop-everything-else critical.”