Seems like an asspull or an advanced form of preta path but the rinnegan was always meant to be opd. Especially when it comes to controlling bijuu.
Its really not an asspull pull if you think about it. Kaguya was also able to pull chakra directly from her rinnegan genjutsu victims. Sasuke just did the same thing.
Well the bijuus were able to transfer their chakra with a mere touch to naruto. I dont understand how he can get their powers with no physical contact unless CT just got an upgrade. It wont be explained but its safe to assume now anyone under Sasukes control can have their chakra stolen.