* Yes it is true that Ubuntu takes the work of others and uses it.
* This is how it is _suppose_ to work. Debian fights tooth and nail for good licensing for the expressed purpose of letting other people use their software and redistribute it without worries. Ubuntu is really just doing what they are suppose to be doing.. reusing, redistributing. Kernel developers do the same thing for 'software freedom'.
(Greg is one of those hugely outspoken pro-Freedom sorts, but yet when somebody else takes advantage of this freedom he takes a shit on them?)
* Making userspace better and improving graphics and UI is MORE important then hacking on the kernel nowadays for a very very large number of users. The sort of users that Ubuntu caters to.
* Making software usable is significantly harder then making software.
Ultimately it's all just petty jealousy. People don't like that Ubuntu isn't doing most of the work, but is getting all the credit. So they are overly critical of Ubuntu. Instead they should just be asking Ubuntu to help users understand the software and positive (and negative) experiences come from far more then Ubuntu.
Look at this way....
Would Dell be supporting Linux on the desktop and improving support for their hardware without Ubuntu? Would Intel be interested in supporting Linux heavily on their new embedded systems if the only user experience their customers would receive would be the generic Redhat-style shit desktop experience?
Ubuntu, for very good reasons, is able to push the popularity of Linux and this has had very significant and positive effects on the whole Linux 'ecosystem'
Ignoring this fact is just expressing a form of willful ignorance.