Needs an ecosystem not just free downloads. If you want free downloads the competition already has that. Woodsmith Shop is a PBS network show with free plans downloads, some of which look pretty nice, although I've not tried to actually build anything from those plans.
As an amateur wood butcher I don't need to download someone else's design to make a very basic boring desk. (whoops edited to make clear I'm not implying their desk is boring, just my simple ones are) What I would benefit from is a simple script that given some criteria such as desired tabletop height, or load limit, or wood thickness, or whatever, out squirts a file with artistic proportions and stylish artistic design and reasonable engineering that I could then cut.
Or squirts out an error message. "warning: 5/8 plywood for a 8 foot wide desk? That exceeds wobbly limitation. Use --force option if you are crazy"
I want to run a script "opendesk --height '40 inch' --toplong '48 inch' --topshort '24 inch' --woodtype '5/8 plywood' and pipe the output into a laser cutter file. Or, frankly, just output a PDF for me to cut manually.