I don't think it can be solved without origin specific permissions - to allow using local fonts and whatnot used on the canvas, at the same time I don't think that would be an issue.
Tesla is operating at a loss, but Model S and Model X are sold at a high margin comparable to other cars in their category. Source: share holder letters.
Wouldn't Let's Encrypt offset any significant benefit of this change? Is it somehow difficult or counterproductive for these sites to add a certificate?