It's a good thing their Intel machines go all the way to 28 Xeon cores and 1.5TB if RAM then...

Sure, and I imagine the ARM ones will in time - but it moves the MBP further along the admittedly already in progress line of it not really being a Pro machine anymore.

For some definitions of "Pro" ;-).

Every professional group has different bottlenecks. For me, the amount of memory is more of a problem than CPU speed and I couldn't care less about GPU, although I like having more screens. These Pros would be a tight fit for me, but other people may want a faster CPU more than large memories, so everyone's mileage may vary. I suppose the next generation will bump it up to 32 or 64GB, so they may be more comfortable for me.

One thing I'd love would be more low-power cores. I don't do heavy lifting on VMs and, because of that, these cores seem like perfect for that little MySQL container. Also, the lower the single-thread performance, the sooner you'll see concurrency issues.