(It blows my mind that SFF cases, used by people needing portability, don't have the weight stat freely available most of the time).
Sorry for that, we'll fix that ASAP.
It's quite a popular use case to use SFF cases for traveling so you don't have to make do with a laptop. When flying, you literally have to pay by the kg, so of course you want to keep weight as low as possible. TBH, I struggle to see the appeal of SFF cases if you aren't travelling with them. Your living space would have to be the size of a small closet to be that worried about your stay-at-home PCs size.
SFF cases are more than just means to travel with something different than laptop.
From what I've seen with backers of first Sentry, a lot of people have issue with having small apartments in big expensive cities, so they have fairly standard sized desks, but they want to use big monitors like ultrawides and have reasons for not wanting to have a big tower under the desk. So it's like small apartments and desks not catching up with the screen size trends.
Other than that, it's the console-size, because putting a tower case next to the TV rack is not aesthetically appealing, and stuff like RVZ01/ML08/Node202 is significantly bigger than console/sat receiver, so the disproportion makes it not look good together.
And obviously enthusiasts and people who want something different than standard towers, something unique standing on their desk.