It seems pretty clear Macs "make sense" in desktops, as well, considering Apple still sells millions of them every year, even if they sell many more million laptops.
And when it comes to PCs, it appears laptops significantly outsell desktops, as well, so this ratio does not appear to be unique to Apple and macOS.
Where Mac doesn't "make sense" is for workloads that require massive amounts of CPU and/or GPU power and you are willing to accept the drawbacks of massive electrical power draw and heat generation those workloads generate. And that is because Apple's market research of Mac and macOS users show those workloads make up a very small percentage of their customer base. Apple are not going to make ~99% of their customer's experience worse just so that ~1% of their customers can have a (somewhat) better experience.
So Apple has three realistic choices to address that market going forward:
1) Continue to fork the Mac and macOS between ARM and x86. In other words, continue to offer the Mac Pro in the 2019 form factor with newer generations of Intel/AMD CPUs and AMD/nVidia GPUs and continue to make a unique version of macOS for that architecture that will more and more become functionally different from the macOS that runs on every other Mac in terms of feature-set.
2) Develop a custom "Mac Pro Class" SoC that, like Intel's Xeon and AMD's Epyc, is based on the same basic architecture as the "commodity" chips, but has unique modifications for those specialized workloads. So a lot more CPU cores, a lot more GPU cores, a lot more PCIe lanes, access to a much larger memory pool, etc. Now, because this will be a unique chip that will both be produced in very low quantities and will differ rather significantly from the "commodity" Apple Silicon SoCs, it will be very, very expensive and therefore the entry-level Mac Pro configuration will almost certainly be over $10,000 and will likely approach $100,000 when fully-outfitted with both Apple BTO and third-party options.
3) Just abandon that part of the market and withdraw the Mac Pro as a model from the lineup and make the Mac Studio as the most powerful Mac you can buy and if you need more, you will have to go elsewhere for your hardware, software and OS.