I guess that big companies use customized versions of the engine, and they probably have programmers whose job is to fix these kind of bugs.
The Witcher 4 should use UE5, and I heard that even EA is probably gonna adopt it (instead of their proprietary Frostbite), probably it’s also more convenient for them to fix bugs in Unreal than mantaining improving their own engines 
I think that’s really hard for an indie developer to publish something with UE5, I’ve had so many problems with it that I love and hate it alternately.
And I wasn’t taking about performances: sometimes I struggle reaching 30fps with a 5950X and a 3080ti, I don’t want to imagine how it is to develop with a notebook…