Isn’t Zen fab’ed on nodes sizes Apple used 2-3 years ago (since Apple pays for exclusive rights to TSMC for latest & greatest node sizes).

Yes. N4 or 5nm Class compared to Apple's N3E or 2nd Gen 3nm. But the gap in IPC remains the same regardless of node. AMD could scale higher or has lower energy usage, it still wouldn't change the performance.

Not only is the Zen 5 slower, it also uses more energy to achieve the its results. Thinking about that the gap is staggering.