Unregulated anticheat software retaining user clipboard contents, sending/uploading arbitrary files, all window titles, all processes and computer and username, and any other IPs on LAN and ARP cache, sending in plaintext across country borders, ignoring GDPR/CCPA/etc.
If you are detected to be a reverse engineer based on running processes or otherwise, even if it has nothing to do with the game, expect significantly more surveillance too, up to and including literal streaming shellcode running from the server at the highest privilege level at any time, none of which you can control.
But are you actually suggesting that the games are keeping data from this activity and using it some bad way?
You kind of dodged the actual part where something evil actually happens.
On a naive surface level of this, it's a game, not your banking account. How much is really at stake here?
Imagine if games like Mass Effect phoned home about the choices you took. You can build up a pretty complete psychological profile of someone based on their gameplay.
If anything, you'll be dumped into big buckets like "buys lots of cosmetic items", "usually makes good choices first", "likes to try breaking aspects of games", etc
I mean sure I guess.
I'm pretty skeptical that this is really occuring though. I mean, to what end?
As someone who runs an online game we have text logs of user actions, yes. They sit there because it's useful debugging info. A server crash happens and we look at the logs of what the user was doing at the time. An exploit is reported and we look at the logs of what the user doing the exploit did so we can fix it. Etc etc.
I really don't know what nafarious thing people imagine is really occuring.