I'm going to guess you're pretty exclusively an Apple user. I think a big part of the problem is that a lot of the people developing FOSS don't have access to Apple's platforms for doing development, and in many cases, even testing. Because of the walls that Apple has set up for it's platform, doing so is often impractically expensive.

I think this is part of what is meant by being slow to critisize. Yes, FOSS often sucks on Apple's platform, but it's also useful to understand the factors involved, and what motivates people.

P.S. The best of luck in your endevors! I think the world of SVG editors could use some solid competiton.