This is a bit of a copy-paste from one of my own tweets, but I think the move to UE5 is more a recruiting move than a technical one:
"Pretty sure The Witcher 4 being on UE5 is for recruiting purposes. ANYONE can take courses and learn UE5, but REDEngine would have to be trained internally after hiring. I think the move is more human related than tech: REDEngine makes FANTASTIC looking games. CP77 maxed is *fire emoji*"
And in a reply to someone:
"Yup! I've SEEN CP77 maxed out, it's easily up there amongst the best-looking games on the market. Part of that is because they implemented ray-tracing pretty well. But nowadays, there's more contract work/remote workers/etc. that requires instant work flow from anywhere"
I think this is so they can expand or contract workers and have them hit the ground running on the project. This allows the workforce to be more fluid and keep the project moving along as well as bring in EXPERIENCED devs in the engine, something not possible on an internal engine requiring years of internal work across their games.
