its more at play here than the CPU core count / IPC etc etc. The subsystem is way faster than the iMac or imac Pro’s. The youtube videos so far do not show real world benefits. I own an iMac i9 with Vega 48 and the 12 core Mac Pro with Radeon vega ii. The difference is perceivable and sometimes unbelievable. Especially in cpu intensive tasks like import/export and filters.
I extensively use photoshop / Lightroom and fcp x. there are days when we are importing 3000+ images off a wedding and the saving in import times / 1:1 previews itself is enough of a justification.
I have had days where a 2000+ image import was going on in Lightroom and I was happily editing in FCPX. Not possible on the iMac 2019.