I was in the exact same situation late last year, and I went with a X1 Carbon 6th Generation. It has been fantastic. Everything just works, and it has probably the best keyboard I have ever used on a laptop
How's the trackpad?
How's sleep mode if you use it with Linux?
I'm still on the fence, but I ordered an iFixit battery replacement kit for the MBP. After almost 7 years (!), it still has everything I need except for the fact that it randomly shuts down when the battery is at 60%...
Sleep mode works great, there is a bios setting for Linux which by default is set to Windows 10, once you set it to linux deep sleep works just by closing the lid, and it resumes as expected.
I do use it with Linux, I have Ubuntu 18.04 running on it and it works great. usb-c charging it amazing, and it works great with my usb-c monitor ( lets me have a single cable to connect everything to the laptop and to charge the laptop ) Battery life is fantastic, the only thing I have to get used to is the CPU in it can burn a lot of battery if you are running it at full load for an extended period of time. When I am running lots of containers on kubernetes it can burn down the battery in a few hours.
I've installed Ubuntu 18 with 0 problems. Sleep works fine, haven't had any issues with wake up. You do need to install some custom software and change a BIOS setting for it to use 'Linux' sleep mode (or something like that). Battery life is 'pretty good', not exceptional like MBPs, but definitely in the 6hr range.
Overall I'd recommend a X1 Carbon, especially since you will spend nearly $1k less on the comparable specs.
Cost me 330 euros from eBay. Pretty good computer for development, but it only has 8gb of RAM.
Nevertheless the 2015 Carbon X1 runs Manjaro Linux with KDE very well, everything works out of the box.
More developers really should consider moving away from MacOS and "fashion" technology, and start recycling older systems. A web developer does not need the fastest most expensive device on the market. Especially not a $5000 MacBook with a bullshit touchbar.