That isn't necessarily true.
Black Desert Online is F2P and sports some of the most gorgeous graphics I've ever seen (
https://www.youtube.com/watch?v=5G6EXTBrwUY ). And they are using an in house engine.
ArchAge is over a year old now, but still sports some of the best looking water I've ever seen in a game. Granted the rest of it doesn't put it as the most graphically advanced game of it's time, but it isn't too shabby either considering it is an extremely large seemless open world. And it too is F2P.
I suppose it helps that they are both made in a country that is dominated by PC gaming so they've never had to make graphical concessions to games having to work on or be ported to consoles.
I also wouldn't be surprised if ArchAge has made the developer more money than GTA 4 or 5 made. And Black Desert is set to potentially eclipse that.
There is no reason Crytek couldn't still focus on developing their engine and keeping it on the bleeding edge even if they completely abandon traditional retail gaming distribution. And we still don't know if they are abandoning that method of distribution or not.
Obviously going F2P doesn't guarantee Crytek success, but neither does traditional retail gaming distribution.
Regards,
SB