The site's down, and you raise a valid point. But:
Even starting from an ETA, there are improvements and variants that can be made. (For example, some Chinese clones of the 7750 added a safety mechanism to the date's quick adjust mechanism. It's a really simple and elegant design change, too.) The open source aspect of this project isn't just that there's a movement, but that there's a development process. Or that's what they say, anyway!
Also, pretty much every non-ETA/Sellita movement in the cheaper-than-Rolex market is just about marketing. The movement offers nothing of interest to buyers if it's just some tweaked CAD files of a 2892, because those buyers would just get an SW-300, which is the same thing [1] with better reliability.
[1] Or not the same thing; there are probably differences just like with the SW-200, but everybody in the market will think that way.
Even starting from an ETA, there are improvements and variants that can be made. (For example, some Chinese clones of the 7750 added a safety mechanism to the date's quick adjust mechanism. It's a really simple and elegant design change, too.) The open source aspect of this project isn't just that there's a movement, but that there's a development process. Or that's what they say, anyway!
Also, pretty much every non-ETA/Sellita movement in the cheaper-than-Rolex market is just about marketing. The movement offers nothing of interest to buyers if it's just some tweaked CAD files of a 2892, because those buyers would just get an SW-300, which is the same thing [1] with better reliability.
[1] Or not the same thing; there are probably differences just like with the SW-200, but everybody in the market will think that way.