You explicitly agree to their TOS and TOU when signing up, and if you violate them (as determined by YouTube themselves!) you're out.
tl;dr: nothing to see here, move along...
Nothing to see there, move along /s
Fact is, when you monetize videos on YouTube you enter a contract with them. If you fail to adhere to the contract (by violating the TOS/TOU, for example) then YouTube has every right to terminate your contract... You're always free to choose another platform that is more aligned with your content/values/actions/whatever...
YouTube is not a Museum
Are you one of those "it's not censorship, just make your own media platform" techbros?
He also just got a strong statement of support from the owner of another large monetized video distribution platform (X fka Twitter). So he can always move his show there.
But you'll be glad to know the UK govt is pressuring Rumble to demonetize him: https://twitter.com/piersmorgan/status/1704808395658727715