Thanks for the input, all. While there are some excellent Windows laptops out there, I'm inclined to agree with AdonisSMU that none is quite like the new 15" MBPs. That makes the question of whether the MBP is overpriced relative to the competition harder to settle.
The Dell XPS 15 UHD seems to come closest to the MBP 15". For $1900, sometimes less with discounts, you can get the same CPU as the base MBP 15", 16 GB RAM, a very fast if still significantly slower 512 GB SSD, a significantly higher resolution but less bright lower-contrast display, a touchscreen instead of a touch bar, a comparable dGPU, good but not as good speakers, a variety of ports but only one Thunderbolt/USB C, more limited ability to run external monitors, poor battery runtime for casual use, better repairability, and Windows, that can run hot and throttle under load. (This is based on reviews, not my experience. Corrections are welcome,)
Whether that's a better value depends on how much you value the strong points of the MBP screen vs the resolution of the Dell screen, touch bar versus touchscreen, the better speakers, the faster SSD, ability to run more monitors, sometimes better battery runtime, more Thunderbolt/USB C ports versus less variety, sometimes cooler running, Mac OS vs Windows, and Apple versus Dell quality, customer service, etc.
I think for most people the Dell probably is the better value. But for many the Mac is still a better deal, even at the higher price.
Personally, I find the larger more powerful laptops like the Dell Precision and Lenovo P50 attractive too, but they're in a different class, enough that comparisons are even more subjective.
