Apple has, rightly, been under fire lately for forgetting about the pro market. This display, in the context of the presentation, is intended to demonstrate that their professional focus is back.
The LG UltraFine 5K which has sort of been the de facto "Apple monitor" over the past few years since they stopped making their own is $1300.
Dell has a 32" 8K wide gamut color accurate monitor (UP3218K) which is higher resolution but doesn't get anywhere near as bright. MSRP is $3900, it currently sells for $3400 and includes a stand.
https://pro.sony/en_FI/products/broadcastpromonitors/bvm-hx3...
So about $11k for a complete editing computer with the power to handle multiple 8k streams isn't expensive at all in the context of those industries.
The Mac Pro isn't a "web developer" machine or an advanced spreadsheet runner -- it's a computer designed for people that actually need that sort of power in a desktop workstation. The last thing people in the AV industries are complaining about with this new machine is the cost. It's a bargain.