That's the thing, the brightness is actually only 350nits on Dell, but 400nits on HP and Philips I've linked; the original MSRP was the same as the Dell, it's only the sale price that ended up being really good on those. So, the only TB monitor in its class actually has worse brightness than many of the non-TB options.

The HP is calibrated and has amazing colours, and it's 90Hz, too, although I keep it at 60Hz.

The Philips monitor is 4k UHD and also IPS Black, same 2000:1 contrast as all IPS Black panels share, so, I'm not sure why you'd get the Dell with the lower resolution and lower brightness at a higher price. The only true benefit of Dell is 2.5GigE and 120Hz, but 350nits is actually a downside compared to 400nits of the cheaper monitors I've listed.

BTW, you've never addressed the UPS issue.

Do any docks at all work when the power is out? How do you take that into account when you need to connect stuff like SSD, kb and mouse? Do you suffer data loss on your SSD because your laptop lacks standard ports and dock use is required that can't be powered by the laptop anymore? Or do you get UPS for your laptop just for the dock? I just don't understand how the dock requirement is not a big deal. I got a laptop simply because it's fanless and has an integrated UPS, I didn't need it to be portable otherwise.