Are you sure about that? Because they confirmed a lot of PS5 features.
That how they do... they first update the Engine for the new generation and so after they keep updating it adding more features and making it better the whole generation.
That is why even being the same major version of the engine TLOUR and TLOU2 have different graphics... one is at the start of PS4 and the other at the end of PS4... same will happen with NDE updated to PS5.
It is the ICETeam if I'm not wrong that works on NDE.
Did they make TLOU1 Factions? I heard originally that the MP was a different team/an afterthought. But then again, later at least, Quinten Cobb was a MP focused ND dev (responsible for the Tactical Shotgun in MP if I recall correctly), and I believe he worked for ND-proper. So I'm unsure whom the OG Factions team were, or if they're responsible for the upcoming Tlou Factions/Online?