secrec the porn upload sites (pornhub being the spot light) ended that for everyone by willfully not managing the legality their content or their users. That precidence in both crimial and civil rulings put all the big regular video & music content providers (not under gov oversight like porn industry) on notice of the vulnerability to legal actiom. Of course there are numerous other reasons that have been mentioned.
As for the solution for the op I am on the same page as @DeletedUser43 comments. Seems to me the easiest simplest solution if you need the content fron youtube is burner account and grayjay or similar. Focus being the "burner account".
@DeletedUser43
You did a very good job of explaining it in your lengthy post (with the bullet points etc ) even if english was your native language. Actually better than many of the younger generations writing ability that are native english even at the collegic level. Its honestly sad. You 100% answered the OP question as I read and comprehend it.
I think you clarified the illegal part as well when it involves stolen credit card numbers etc for getting past pay walls or even those that use credit card as part of their account setup/verification process where they charge nothing or do a $0.01 charge back to confirm CC is active and not from a CC number generator.
I do wonder if a visa gift card could work as a legal way for the CC confirmation part. I have used those in the past when I was not sure of the security on a site I was purchasing from. Now my CC provider has one time use CC numbers for online payments that link to your primary CC account #. The VISA MasterCard gift card also work for anonymity if they purchased "correctly" and are accepted in the POS provider.
Either way do not let others comments frustrate you. (Not specific to this thread) There are ever increasing numbers of people that believe they are entitled and demand nothing less than to be spoonfed info they are too lazy or incompetent to research themselves. They will even lie claiiming they looked everywhere and not answer was to be found yet a simple search engine query has the answer in the first few links and 1-5 mins of reading.