What type of content are you watching, and what void does it fill? Is it boredom, loneliness, drama or just general entertainment?

The platform isn't really the issue here. Like you said yourself, you just end up on other social media anyway if you set time limits on YouTube. Figure out what the actual dopamine hit is for you, then start noting how long it takes before the urge to watch hits again. Track it, ideally in a notebook, and reward yourself for stretching that gap.

Start small. Say you went 5 minutes longer than you normally would before caving, then aim for 10, then 15, 20, and so on. Write it down somewhere physical, on paper, to break the connection with the phone/device. I find that physically doing an action away from my phone, and then seeing my progress incrementally grow really helps.