Well those are different distros to start with, and ubuntu is the only Linux distro that either approaches user-friendlieness for a typical computer user or has notable community support.
Debian and Fedora have those characteristics in common.
Microsoft only recently stopped selling Windows 3.x, Windows 2000 is still supported. Many banks and buisnesses continue to use decades old OS's with third party support. I'd therfore say that MS withdrawing support isn't that much of an issue, compared to ceasing development of the OS.
This is irrelevant to my point. I'm not saying that they
will withdraw support, or that they
are withdrawing support, but that they
can withdraw support. And you're perfectly okay with them having power over their users because you don't
think they'll abuse it?
Again that leaves out many other questions such as the reliability of the various companies and whether they'd have any motivation to work on the software in question. For example would either Red Hat or the Debian Project support it over their own distributions?
GNU/Linux is an operating system, Ubuntu is simply one distribution of it. If support for Ubuntu were withdrawn, I would simply choose another distribution. I'm already considering a switch to Debian because the last time I upgraded Ubuntu, it installed a non-free package without asking me if I wanted it installed.
NSA backdoors.
I just looked that up, and I wasn't aware of it until now, but I'm not sure how you think it supports your point. Free software is fundamentally incapable of hiding anti-features from the user in this way, because anybody can see its source code.
As to their motive for this, it seems that even many top Microsoft programmers are unaware of it due to highly compartmentalised development, according to
this article.
Hmm, it's odd that if my computer, running windows 7, ever needs something it doesn't have, I'll probably be able to find a program I can use that'll do it. If not, I could write one.
And Microsoft could stop you running it, if they wanted to. But that's irrelevant; while you can add functionality, you can't remove or change what the operating system itself is doing. You can't, for instance, look into the NT kernel and see exactly how it is doing its job, and modify it to suit your own purposes.