So there's probably at least some calculation where they have to decide how much effort they're putting into cracking down on these things, simply because on the one hand they don't want to anger Hollywood and music labels, and on the other hand they don't want to kill off 3/4 of media analysis content on the platform.
There's also the fact a lot of creators will deliberately turn a blind eye to people reusing their video footage so long as they credited in return. For a lot of them, it's less work to just let people figure out how to get the footage from their channels than to set up a third party hosting service where you can officially download them.
Interesting to hear about the terms of service provision though. Wonder how well it would hold up now given that a lot of modern outlets use donations or paid subscriptions for financing rather than ads? I can see an outlet like 404 Media covering YouTube downloaders at some point because of that.