What exactly is their system for determining optimal layout? It must be disclosed in detail. They can't just claim that any approach like that is theirs.
Unfortunately your second sentence is not correct; patents do this overclaiming game all the time.
(not a lawyer, co-inventor on three patents so I've been through this, unfortunately as I didn't want to participate in that system, consult a lawyer before doing anything rash).
The claim matters, not their detailed description. The most harmful patents work that way: describe in detail a specific implementation, but write the claims to cover every alternative implementation you can think of.
Unless the system was attempting to cache-optimize the memory, then it is probably going to infringe. So basically everybody.
Several already existing unreal games already use ecs. I saw a tech talk about Conan exiles for example. It’s just not part of the engine. Can’t find the talk, it was an epic event, but they advertise it in job postings
https://jobs.funcom.com/jobs/975839-gameplay-programmer
Edit: the video https://youtu.be/QlKXPBFh5BM
I guess this will be a major roadblock to Unreal Engine offering such an automated ECS system, which is a real shame. There are certain types of games which do need ECS to make viable use of computing resources (simulations, etc). You don't see many of those on Unreal now and I guess you won't for the foreseeable future if this patent holds.