I think I first heard someone complaining about the term user maybe 15 years ago.
Sometimes a user isn’t even a person; corporate bots are known to run accounts on Instagram and other social media platforms, for example.
Maybe the term "user" needs to not only refer to humans. When I first heard objections they were more centered around making it sounds like they were drug users. The reality is we are learning that user is a pretty good label. Over the years it has occurred to me that many users behave like bots. Users that are indeed humans. What I mean is that they are behaving in very predictable and unnatural ways. Way a human in real life would not behave. So maybe user is the right term after all. I dunno.