You are asking me to debug something that I can't see...
They wouldn't structure the code diffently no, but if a task finishes faster/slower than expected or than one SKU that could easily create these issues.
It's irrelevant to bring up the Windows version, it's not the same codebase even if 90% is shared the issue could be on the platform specific code and who knows maybe IT IS there on some systems but they were never able to replicate it.
I'm not asking you to debug anything just saying it wouldn't make sense given the information you have to be concurrency issues that are not hardware related. When you debug it's a good idea to have an idea of what could be the issue to know where to look at least.
I think you've misunderstood what the resetera guy is saying and he has not read the developer quote with the exact issue that was given by the devs later elsewhere.
The resetera guy seems to think it's a technical issue affecting the xbox platform as a whole. Ie they are running into bugs on X and S, whereas it's not. in the later quote it's made clear that the X and S co-op do not run to the same standard which is a requirement to ship.
The resetera guy siad:
"
Different hardware and SDKs can expose different issues in an engine, it's just that simple (as it is maddening). It could be something like the
difference with in DX12.. (They haven't talked about what the problem is or even alluded to it, so I'm just spit balling a possible scenario.)"
Now if you're saying it's not an API difference and we have information that we are not talking about different platforms anymore i.e. we have the same SDK/compiler for series x and series s, what remains?