Terrible advice. Not only youtube will precisely fingerprint you, nordvpn/tesonet/oxylab will also get data on you.
NordVPN only sees that you connect to YouTube, they do not see the pages or videos that you are looking at, and from the perspective of YouTube, they only see requests from a very popular VPN where are millions of users.
If you use the "privacy" instances, these "privacy" websites and Cloudflare knows precisely which videos you are watching.
Also IIRC for youtube, alternative frontends don't tend to rely on someone else's endpoints.