That AMD slide (in the conclusion) claims their switching fabric has some kind of bypass mode to improve latency when utilisation is low. So they have been rea

That AMD slide (in the conclusion) claims their switching fabric has some kind of bypass mode to improve latency when utilisation is low. So they have been really optimising that IO die for latency. NUMA is already workload sensitive, you need to benchmark your exact workload to know if it’s worth enabling or not, and this change is probably going to make it even less worthwhile. Sounds like you will need a workload that really pushes total memory bandwidth to make NUMA worthwhile.