I think the United States Web Design System might fit in that category. It's made by the US Digital Services, and describes itself as "A design system for the f

I think the United States Web Design System might fit in that category. It's made by the US Digital Services, and describes itself as "A design system for the federal government. We make it easier to build accessible, mobile-friendly government websites for the American public." It's a well thought-out framework and from what I've read, accessibility was taken into account in the very first stage of the redesign of the new V2 https://designsystem.digital.gov/ https://designsystem.digital.gov/ Totally free since it's paid for with US tax dollars.