It is about the same price or more expensive to get an equivalent windows machine, the Thinkpad P52 is similarly priced if you go for those specs.
I think part of the issue is that you don't have a choice of specs. If PCI-E SSD speeds are enough for you, you don't have a choice to save the money on it. If you want to go for a cheaper 4-core processor with higher clock speeds and put the money into more/better RAM, you can't make that trade-off.
I do agree that macbooks are pretty good value for the components you're getting, but I think unless your view on what you want in your computer matches what Apple will give you then you will end up "wasting" some money on your machine.
it's a pedantic point I'll make, but one that's important to articulate: Apple hardware has incredible build quality- and you pay for that. An equivelant build quality Windows laptop will cost roughly the same.
The Entry level Apple MacBook pro 15" is £2,349.00 with:
256GB Storage (m.2 SSD, high speed))
2.2GHz 6-core 8th-generation Intel Core i7 processor
Radeon Pro 555X with 4GB of GDDR5 memory
16GB 2400MHz DDR4 memory
Retina Display,
--
The same spec DELL Precision 5530 is: £2,481.49
256GB M.2 NVMe PCIe SSD Class 40 (Much slower)
Intel Core i7-8850H, Six Core 2.60GHz, 4.30GHz Turbo, 9MB 45W
nVidia P1k
16GB, 2 DIMMS, DDR4-2666MHz SDRAM, Non-ECC
15.6" Ultrasharp UHD IGZO4, 3840x2160, Touch, w/Prem Panel Guar 100% color gamut, Brushed Onyx
--
So, more powerful CPU, slower storage and less pixels with a touch screen. -- For the same price.
The issue when comparing price is that it's often Apples (heh) to Oranges, Apple only sell high quality hardware thus the cost to play is higher.
(FWIW they also charge too much for upgrades; but this is just smart business as those who need that much power are willing to pay)
(PS: I actually own a Precision 5520 and I love it; I don't buy into the Apple hype train but I don't buy into the anti-apple hype train either- all systems should be weighed on their merits but my point is that price is often an unfair metric when people talk about laptops due to the abhorrent build quality of most laptops)