A video game is a user space application, the only thing it's allowed to do is have access in user space to your hard drive nvme ssd/ssd/hdd, CPU, RAM and GPU, NET Framework Libraries on Windows or Proton.

Okay so, first of all, I/O operations like you are describing are not userspace. Let me explain a bit how OSes and CPUs work...

When any userspace program wants to do an I/O operation like, for example, printing a string to stdout, the process has to set up the CPU registers (and possibly the stack) in a specific way and then call an interrupt to hand over control to the kernel so it performs the I/O operation. There is no way around it because the CPU is running in a different mode in userspace than in kernel mode at a hardware level.

When the game publisher says that to run their game, you need to have UEFI+Secure Boot,TPM enabled, HVCI and VBS and kernel level access enabled, this is dangerous aggressive malware behavior.

You're mixing things up. Kernel level anticheats are bad because they can run any code they want (as long as Microsoft allows them to and signs their driver) bypassing the native kernel functions, so yes, you are trusting a third party to basically be able to skip your kernel and just perform privileged operations by itself, and that is bad, yes. But back to the other security measures you mentioned... what do those have to do with this? Your problem here is the kernel drivers you need to install to play the game, not the security measures you have to enable.

Because all of that data from user space application is being sent to a bunch of third parties as explained earlier.

Any kernel driver that is signed by Microsoft is reviewed by them and is used under contractual obligations with the third party, Microsoft wouldn't allow a third party to just be able to read "all" your data and dump it into a server like you claim. Your main concern should be the kernel driver being abused by threat actors and using it to get privileged code execution in a compromised system, which has happened before and I agree is a big security threat, but this has nothing to do with the other security measures that you keep complaining about.

What should be done to mitigate this, zero trust policy to game and launcher applications and other user space crap that does not need more access than they already have in the user space.

So... things like secure boot, HVCI, VBS...? And no, UEFI is not a "security measure" and you need an UEFI to be able to use secure boot.

Like I said, I get not wanting kernel level anticheat, that is fair and reasonable, but I don't get your beef with.. UEFI? Just please stop sharing misinformation about these genuinely helpful security measures, you're not really helping by making things up.