This seems like an incredibly high bar/expectation to set for themselves, and while I'd love to see them succeed, I don't have a lot of confidence. The fact that they've decided to start out building desktops really solidifies that doubt. I just don't see a world where there is a demographic of people that both know about System76 and want to use a non-standard OS on a desktop computer, but also aren't familiar with building one themselves. In an enterprise environment, I don't see them making a huge dent either when many companies will already have deals with major enterprise manufacturers for desktop units, which are fairly easy to turn into GNU/Linux machines as is. It just seems like a sinkhole trying to pour effort into a form factor that has become incredibly unpopular over the past few years, and also (very publicly) setting the expectation that this effort will lead to the "the Model S of computers".
From a personal/consumer standpoint, all I want to see anymore is a competitor to the Macbook Pro, with a comparable track pad, display, keyboard, battery life and form factor. I'd love to move away from my MBP, but the closest competitor I've found is the XPS 13 and, while it's a great laptop, just doesn't hold a candle to the MBP in a few of those areas. I wish System76 luck and would love to see them prove me wrong. This press release, so early in the process, just seems like a lot of pressure for the company to live up to, especially based off of their past offerings.