If people aren’t in an office, around other people, their aren’t really a lot of opportunities for random nonsense complaints to come out. And if they do, there are email messages, recorded video calls, and so on that can clarify reality far easier - meaning HR’s job is made clearly irrelevant, and clearly demonstrates it is a mop job for a handful of busy bodies that cost the company more in efficiency, than they earn the company after accounting for their wage.