I'd assume he takes issue with Canonical's practices, like the Amazon search tie-in, etc.
As far as I know, Amazon search is only available on the default Ubuntu install. No fork has ever adopted it what so ever.
I don't see how that is relevant. It's enough of a vile business decision to some that it might deter them from even using any Ubuntu-based distro out of principle.
They've admitted their mistake and are/have rolling/rolled it back. No need act like they are the anti-christ.
I'm explaining the mentality of the Debian-only crowd, not my personal beliefs. I've got several Ubuntu-based chroots on my Chromebook.