If you quit YouTube then you also quit all the content on YouTube that isn’t elsewhere. The best solution if you still want to use it is to use 3rd party apps. Personally I would actually count that as having no reliance on Google in particular anymore. If a video platform owned by Google wasn’t the most popular then it would be another platform. I don’t think you should think of 3rd party apps as YouTube frontends, but rather, apps that scrape videos hosted on Google’s servers.
I’d look at it in regarda whether or not Google can get your data (or more somply), do you volountarily connect to Google’s servers: if not (Piped/VPN) I’d count that as being degoogled. If yes (Invidious etc.) you’re still getting the video from Google servers (albeit without ads) but Google still gets their grubby hands on some info about you. By ‘volountary’ I mean if you block connections to Google with e.g. Noscript and keep google enabled (be it tag manager, gstatic, fonts or user-facing services like Youtube). If you have to enable gstatic or tag manager on a few sites because they’re broken, I’d say that’s involountary since it’s not your reliance on Google showing as much as it’s the developers’.
Being 100% disconnected from Google servers is outright impossible these days.