Hear me out, how CTless Yuji can eat and get other's CTs?
CT works as a medium, like Geto used to eat curses and later manipulate them through his CT.
For this to happen, Yuji needs a CT that works as a foundation and allow him to eat his brothers and take their CTs, no?
I am implying that Sukuna's CT is already in play and it allowed Yuji to eat his brothers and use their CTs. Maybe a reach.