Yes, and I've seen it happening. Usually it doesn't instantly brick every PC, but it can sometimes brick certain PCs with specific configurations. Then it will be silently patched without acknowledgement for the bug.
I've seen it mess with (and crash) graphics and network drivers, rendering PCs useless until forced reboot. It can also mess up other games, processes, and even updates.
People have been warning gamers about kernel level anticheats since they were introduced, because no userland code should run with that level of privileges, period. However, people still installed those games not really understanding the threat, and that's why we have so many games with a kernel anticheat.
You don't give your house keys to your home security system provider. Giving kernel access to anything, even if it's for your own good, is dumb. People don't understand the risks that come with it. People just think what the companies tell them to think. As a matter of fact, there are still cheaters in valorant. Vanguard isn't perfect, it can still be bypassed. VAC works fine for what it is, and it could still be refined. It bans more people monthly than Vanguard.
The biggest reason for kernel level anticheats is your sweet sweet data and more control of your computer. You don't need them. We have been playing online games since the 90s, and none used kernel anticheats. It was never necessary to sell your computer to Tencent in order to play a game which, again, still has cheaters.