Apple does appear to be tailoring their Pro-labled products to the feedback they are getting from the Pro Workflow Teams and those folks are probably closer to the upper-end of the user spectrum than the lower.
The Pro Workflow group only does small scale (highly likely statistically insignificant ) sampling. The feedback comes from Apple hiring folks to do on site projects. That is only going to be a relatively low number of contractors. And probably zero controls for demographics sampled ( it is also likely folks who Apple filtered out to be highly Mac friendly and trustworthy enough not to talk too much).
Apple stopped reporting units sold and started focusing reporting on margins. That's highly more likely one of the drivers here. More "fat, juicy" products over a maturing user base. Price sensitive customers dropped. Chase customers with deeper pockets and/or less price sensitivity.
So by default, that should mean that their needs represent a majority of general user's needs so what Apple makes "for them" should also work "for the rest of us".
It isn't going to pragmatically work if it is out of budget. Having an 1.4KW power supply when only really need a 700-800 W isn't going to work "well" for someone throwing extra money at that extra 700W for no material impact.
That being said, as
deconstruct60 has noted, that means the final product will be more expensive and that price may very well put it out of the league of many of "the rest of us". The Mac Pro appears to be the extreme case for this where the base model price and configuration is of effectively no value,
The base has effective value for some. It just isn't aimed at "average' folks. Wrapped in a rack enclosure and allocated to running a hypervisor with 3-4 VMs is probably a good value match. Don't need a large boot hypervisor drive. Can add either higher end networking or storage for the VMs (that can be provisioned by a couple of slots ) and if mainly headless grunt work for the VMs then GPU makes no material difference.
Is that configuration going to help John Doe with a MP 2010 with 4 HDDs and 2.5" SSD boot who just wants a tinker box and grab the latest GPU off the shelf from the Fry's discount bin? Nope.
though the upper-end is as close to "no limits" as a Mac has ever been.
If the Pro workflow group has done anything, I suspect it is more likely is skewing the Mac Pro farther into being a LogicX and/or FCPX machine. The projects that Apple hires folks do are extremely skewed to those to apps or at least the solution space those apps play in. That is acutally not going to be "no lmits" but it is a limited solution space being explored.
Closer to what they have is chasing a customer base that has has "no limits" on what they spend ( or pragmatically are largely spending other people's money). This Mac Pro has limits. There are a bit higher than what they offered in 2010 but not really a "biggest of big" . If try to slot up several x16 cards and use them concurrently for high bandwidth will also probably see some limits on the other slots/ports.