I'm similarly worried about it not working out in the end (perhaps because they have my money now!), but the part that most gives me hope is that these guys have already worked out how to run a successful open hardware business at lower quantities. Given the terrible track record of others trying this route, that business knowledge seems very valuable. I remain hopeful and excited :)
On a side note, when will they add etnaviv to Mesa's features.txt? So far it can't be shown in Mesa matrix: https://mesamatrix.net