Having just (metaphorically) signed up on D.Tube, I was initially very excited about IPFS because I believed that D.Tube would serve the videos through it, and contrary to my expectations, watching videos on this competitor of YouTube is actually just as fluent as on YouTube itself.
It was therefore quite disappointing when I tried watching one of my videos via a local IPFS gateway: it's slow as hell and totally impractical. But, how could this be if watching the videos from D.Tube was fluent? The disappointing solution to this paradox is that D.Tube doesn't actually use IPFS to stream videos, despite the prominent mention of it on its homepage. Granted, when you upload a video it still gets uploaded to IPFS, but the streaming happens from D.Tubes internal server farm, at least if I understood this article correctly: https://nannal.com/dtube-past-present/

So yeah, IPFS is no replacement for BitTorrent. Not even close.