The problem is: it kinda fits the timeline, AMD developed and then released GCN, two years before XO and PS4 release, then stuck with it for the whole PS4/XO life cycle, refusing to dramatically change it or break away from the formula, until almost two years before the PS5/XSX release, when they developed RDNA which -coincidentally- is also the basis of PS5/XSX.
Before that AMD had a lot more liberty to change architectures, they went from VLIW5 to VLIW4 to GCN in the span of just 4 years (from 2007 to 2011), but then they stuck with GCN from 2012 to 2019, which is a frigging 8 years period!
It seems that at the very least, AMD stuck themselves into a lockstep rhythm with the console release cycle, only changing architecture when the console cycle is about to end, and seems RDNA is heading toward the same fate too.