My reasoning for them not being canon isn't that I don't like them, though I do encourage people to compartmentalize things in that way rather than worry about canon. I think I made that point clear. Its the proprietors of Homestuck who create these distinctions between what is or isn't canon, and though they rarely comment on the topic directly, the actual contents of the works seem to skirt around the idea that they're canon at all. Even the very format of the epilogues, the only post-canon, non-hussie work to be hosted right next to the original webcomic, kind of serves to separate itself from the source material.

It's like when they make an animated batman movie which adapts one of the comics. It assumes some foreknowledge on the viewer's part, it assumes that certain events from those comics have happened, but by design they aren't intended to contribute to that canon, even though it introduces new material, like batgirl sleeping with batman. They're like, simultaneously self contained and also reliant on the source material, if that makes sense.