In 2 words: YouTube sucks (sorry) – especially after the last change of their terms of service
However: YouTube has some huge advantages concerning mobile devices. I have to admit: They saw it coming and put a lot of improvements into that sector.
e.g.: With the YouTutbe App - it's real simple to stream a Video from your mobile to your TV - in HD.
To catch up to that, DTube has some work to do. Well, I have full confidence in that, that’s why I quit uploading to YT.