I disagree with Apple really should have just been honest with its pro users and said "We no longer care about you,"'.They've abandoned a very specific and shrinking segment of pro users, but the vast majority of pro users are covered by today's lineup with Mac Studio at the top.
Depends on what you mean by covered. Can they do their work? Yes. Are they negatively impacted by hardware limitations? Also yes. A lot of professionals would be willing to pay extra for ECC. The fact that Apple doesn't offer ECC makes their machines less than ideal for use cases where a crash would be expensive. The fact that a lot of pros put up with crashes doesn't mean they like the situation. It just means that they dislike it less than switching platforms and tools.
But the pro users I was specifically talking about here are the ones doing high-performance computing tasks involving GPUs. Their only real option is to change platforms, because even though the new Apple Silicon CPUs are great in terms of performance per watt, the wattage is really low, so if you genuinely need boatloads of GPU, to the extent that Apple was still in the game without NVIDIA support, they completely dropped out of the game when Apple Silicon dropped support for AMD. At that point, Apple computers became nearly useless for most modern high-performance computing/AI workloads, people doing large-scale 3D video rendering, etc., because they're underpowered as shiped and can't be expanded with more GPUs, and parallelizing work across multiple machines is way more expensive and not always practical.
One minor peeve - what is "pro" today? Most office workers can do their work just fine with the some of the cheapest equipment you get - isn't that "professional" enough?
The historical definition of "pro" is people who are running software beyond what a typical user would run. Web browsers and productivity software (word processors, spreadsheets) are not pro apps; they are business apps. Pro apps are mostly things like high-end photo editing (think Photoshop/Pixelmator, not iPhoto/Capture One), 3D modeling, audio/video production, etc.
Even most developers can do most of their work on laptops these days - and if they need more horsepower, that's likely to be on the server side anyway. Don't they count?
Developers at least arguably fall into that category, though they are borderline, because they don't have huge storage requirements or huge compute requirements. Developers can do most of their work on laptops, though Apple's non-Pro laptops are pretty thermally throttled, so they will be miserable. And developers are probably the group who care most about ECC RAM, because they understand enough to know why it matters, but they still often use laptops because they don't want to be tethered to a desk. It's a tradeoff.
And what about project managers, lawyers, and CEOs - aren't they "pro" either?
No, and they never were. While the users might have professional occupations, their computing requirements are indistinguishable from a high school student. "Pro" in this context doesn't mean "users with money". It means "users with needs that exceed typical requirements". :-)