Possibly it's also self-preservation by the people involved. I imagine that even the YouTube developers and project managers hate watching ads. A solution only for them would probably look bad to the outside.
In most countries, any YouTube user can pay a subscription fee to disable ads. It's called YouTube Premium: https://support.google.com/youtube/answer/6308116?hl=en
This has existed since 2015, so presumably Google employees have it on their personal accounts.
source: ex-googler