Unfortunately, I don't think there is a mature enough FOSS video streaming platform. it turns out video hosting is really really expensive and complicated.
I recommend trying out GrayJay, it has YouTube and it's most popular alternatives in one app, this way you can still watch folk from YouTube and support other platforms
If you are a little experienced and know how to deal with Docker, you could self-host Invidious yourself on your local PC or laptop. Works fine for me for multiple months.
You'd be still using the videos of YouTube, but without their ad-flooded UI.