Sure, there are plenty of differences, but these are mostly the equivalent of vim vs emacs - if you're good enough you can make either work. They're mostly just matters of personal preference.
Though many users don't have the benefit of your level of experience. And, there should always be room for new users benefiting from Linux. So Ubuntu's tended to focus on being a Linux that works "by default" on the desktop and make sensible choices for developing in the Cloud.
The distros certainly have a lot in common, but each has its quirks and idioms, and once you learn them, it's annoying to have to bother learning another. Like, once I've memorized how to do a lot of things with RPM and Yum, it becomes "friction" to suggest that I learn to do the same things with apt.
I don't have any problem with Ubuntu, and I think it's fine for new users. I stick with Fedora really for two reasons:
1. The aforementioned familiarity.
and
2. They are more ideologically committed to software freedom, in terms of not shipping things like mp3 support, where you have patent encumbrance issues. I have been trying to gradually shift my life to a place where I don't need that stuff at all, or where I do, I use OSS / free software to interact with it. I mean, I'm pragmatic enough to use VLC to watch DVD's, but I don't go out of my way to use any content that isn't in a free format, etc.
This is exactly why people were screaming at Red Hat back when they decided to kill their (then) consumer offering, and later when they started actively eschewing talk about desktop Linux. Everybody knew that developers drive adoption of server OS's and that once developers started moving away from Red Hat derived distros on the desktop that they would eventually start moving away server-side as well. But I guess the higher-ups at RH either didn't believe, or didn't care.
Personally I still use Fedora as my personal desktop OS and mostly run CentOS, Fedora or Amazon Linux on servers. I never saw the appeal in Ubuntu. From what I recall, their main claim to fame had always been "we pre-ship all the proprietary audio/video codecs that RH won't ship" and the supposed superiority of apt over yum.
I use Ubuntu on the desktop on my work provided laptop and it works well enough, but I don't see any particular advantage over Fedora. And I prefer yum (now dnf) to apt, so I doubt I'll switch anytime soon. Still, if RH cares about this sort of thing, they really should start embracing "Linux on the desktop" again.