Cutscenes in ND games have never been CGi, they were always in engine, meaning it was the assets running on the real engine of the game.
Some even were already real time, the one everybody knows with seamless transition to gameplay. The big elliptic kind were pre rendered.
Now if they had to record all their cutscenes in high quality, high bitrate 1080p60, it would take an insane amount of space, specially to digital standards. Actually they have no other choice than making everything real time, like already in remastered TLOU.







