I can only speak for myself, but I was thinking of getting a Galago Pro around a month and a half ago, and got cold feet because it wasn't quite as open as I wanted it to be. I ended up waiting because I don't need a new dev laptop yet.
This announcement has cemented that I'm going to get one, although I'm going to wait for a bit to let their first users of the new firmware work out the bugs. ;) System76 has a really good reputation for QA, so I'm sure it will be a quick process.
It's my impression that System76 is genuinely committed to free (libre) software, but have pragmatically balanced that with a commitment to creating a high-quality product. As other have said, I want a plug and play Linux experience. Ideally it would be completely libre, but none of the completely libre options out there are good enough (particularly, with hardware integration) for me to justify the loss in productivity. This is a good almost-completely-libre option which fits my needs.
The entire company here is pretty well focused on making everything open, because we believe it truly makes a better product. Many of our customers agree with this philosophy, and so for them this kind of thing is definitely a selling point. For people who are less focused on it, it might not be, but it's definitely never a bad thing.
Not to mention the fun you'll have setting up the wifi and the especially good luck getting multi-touch support work just right.
I only replaced it because I decided I wanted to go the "ultrabook" route and have an i5-xxxxU processor but get 12+ hours of battery life. I got a T440s, and ran linux on it, ofc.
I'm curious to hear from an actual buyer on why they purchased that laptop when there are so many linux friendly options available.
For web dev I've been running ubuntu on a virtualbox on my macbook pro for years. It's pretty much just as fast as my fully specced out desktop.
Consider the fact that hardware wise they seem to be seriously lacking. All of their laptops have a 1920x1080 display. My 6 year old macbook has a 2880x1800 display. 6 years old!
There are a ton of linux friendly options on the market now with 4k displays and even OLED displays.