At the scale youtube does things it doesn't really cost them much. They actually have the servers, the bandwidth, often the power. It's not like they get to sell a server if enough people leave. The savings probably do not even justify the effort (=cost) to unplug the server. And they still get many other benefits of having you as a user (getting to profile you, getting to push propaganda, getting to sell your information, maybe you send videos to friends who don't use adblock, maybe you buy merch from creators making creators happier on their platform).

On the other hand this enshittification is ruining their monopoly, other areas of business (if you don't need youtube, maybe you don't need a chromecast? If you don't need a chromecast, would you buy pixel phone, that can only do chromecast if samsung can do hdmi? Maybe you're done with android? And if you're on iphone, are you still using google maps, photos, search, keep etc?) and curing people who are addicted to the platform.

The eventual consequence of enshittification is always platform death. Which would be amazing, sadly the next platform is going to repeat the cycle.