Well the whole point is to be invasive. The idea is to lock down the PC into a console-like platform. Without turning on TPMs, secure boot, and remote attestation, the only way to make sure the user isn't running modified code somehow is to effectively rootkit their system and spy on everything.

The anti-cheat stuff runs as part of the OS, so the company can do pretty much anything they feel like. I'd assume they only bother with screenshots on suspected cheaters, while they're playing. Otherwise it's a waste of effort on their part. But if you don't trust them to handle screenshots possibly containing snippets of IM, then you shouldn't be running their binaries as root.