Now things get rather different with "desktop" solutions. The Mac Studio line is already a bit expensive for the specs, although they pack a lot of power in a small package with relatively low power consumption.
A decently powerful desktop PC with quality components will also be in the $2K range easily.
Things start getting really unreasonable with their Mac Pro line - it's probably the closest to what you are talking about here, and yes prices are really, really high.
But getting a similarly spec'ed system at 10% of the price of a Mac Pro? If you're buying used parts, yes (but then comparing used stuff with brand new stuff is not reasonable). If you're building one with only new parts, it's not likely. Maybe more around 25%-30% or something like that - still much more affordable, admittedly.
The Mac Pro, and now Mac Studio, are good value if you need the things that are in them, such as powerful GPUs and masses of fast I/O.
As a programmer, not a video editor or animator, I
don't need that stuff -- I just need a fast CPU and a decent amount of RAM with some kind of video card that can throw a lot of high quality text up on a 4K screen and enough GPU to play YouTube (and Zoom...). And a TB or so of storage, but it doesn't need to be stupidly fast.
Way back when (2010) my then employer kindly supplied me with a top of the line 8 core 2.26 GHz Mac Pro to use to build their code (Firefox). It was pretty damn expensive. And, sadly, enough of the build process is single-threaded that it wasn't particularly fast. I built my own quad core i7-860, Hackintoshed it, and overclocked it from 2.8 to 3.4 GHz and it was a lot faster than the Mac Pro FOR BUILDING SOFTWARE. And cost a lot less too.
Six months later Apple came out with an iMac with the same CPU. That would be perfect for my needs, except 1) I already had the ugly PC tower, and 2) the iMac came wth an amazing super high quality 27" screen which is great, except that every time you get a new iMac you have to pay for a new screen. At that time I had an Apple 30" 2560x1600 screen which I'd bought 2nd hand and used with a series of different computers for nearly ten years.
When the i7-4790K came out I built a Hackintosh using one of those. And .. six months later Apple came out with an iMac with the same CPU.
Same story when I built my next machine (reusing case and power supply and ...) using an i7-6700K. Six months later Apple made an iMac using it.
And so on ... Apple has even sold iMacs with 8 and 10 core i9s, though by that stage my custom PC was a 32 core 2990wx ThreadRipper (which I use to this day).
In Core2Duo days you could buy Apple's fastest CPU in Mac Mini form. That's perfect for me. As easy to transport as a laptop, but much cheaper. Plug it into whatever screen you want, wherever you are.
But as we got into i7s the Mac Mini fell behind (and NUC wasn't any better).
With Apple Silicon, you can again get Mac Mini with pretty fast CPUs.
I'm still using (and typing this on) an original November 2020 4+4 core Mac Mini with 16 GB RAM. But you can now get a Mac Mini with up to 12 cores (8 performance plus 4 efficiency), which makes a pretty decent developer machine. With 32 GB RAM and 1 TB SSD that comes to $2199. Getting the same specs in a laptop needs a 14" MBP for $2899.
Or, incidentally, a base Mac Studio with the same CPU and RAM and SSD is $2199 exactly the same as the high end Mac Mini. But you can also double the CPU to an M2 Ultra with 16 performance cores (and 8 efficiency), in which case you can up the RAM to 128 GB or 192 GB. That does start to get a bit eye-watering -- $4799 with 128 GB RAM.