I remember the last Mac Pro and iMac delay. It was Sept. 2012, Mac Pro hadn't had a true refresh in 2-3 years, almost as bad for iMacs. I needed a new comp or I'd lose work. Since rMBP was the only new Mac, I spent $3k on one, with ghosting and all. I just wanted a desktop.
Here we go again... Mac Pro is probably on its longest refresh cycle ever and iMacs are old and outdated. This time I learned my lesson and built a PC.
So to answer the OP, a new Mac Pro would generate discussion. But things won't get better, it will only get worse. The next refresh will be 4 years, then 5 years, then discontinued.
This is not a NEW pattern. This pattern is at least 5 years old. Life is too short to lie to myself about a computer company; time to accept and move on.