There largest group of “pro users” but not their largest group of users. But realistically, does anything about the Mac Pro seemed like it was designed for development?

As a primary purpose? Hard to be certain, but I'd say no. The base configuration is in some ways ridiculously overpowered for the typical developer, while missing some easy wins.

It looks like a great machine for developing software (if you can afford it) but all of its strengths as a development machine look like simply side effects of video editing machines needing lots of power. There is no design or feature on it that I can point to and say "this was done for developers". There are many that were obviously done for video -- like a $2000 FPGA option that's only good for 2 intermediate video codecs.

I have no inside information here, but I suspect that Apple sees the MacBook Pro as the Mac aimed at developers, not the Mac Pro. MBPs are more common in Silicon Valley than roadside poppies. So while the Mac Pro was the first stop on their Hardware Apology Tour,† the 16" MBP is the "please stay with us, developers" machine: fixing the keyboard, increasing the performance substantially, and not raising the price.

†Not that they'll actually ever say "I'm sorry" out loud, but it's pretty clear they're rolling back some of the late stage Ive-isms. Yes, I know they kept the Touch Bar and didn't add ports, but I think they're all fully committed to USB-C as the Way Of The Future™ and, uh, somebody high up loves that damn Touch Bar.