In your opinion, do you still think Ubuntu is still the best option for less experienced developers and end-users?

First, disclaimer: I don’t have a good grasp on the derivatives currently around, so there may be good options besides what I mention.

I think Ubuntu (or distros based upon it, e.g. Mint) may be a good distro for peoples who barely know how packaging system and repositories work, and for those who doesn’t know how to use search engines (or doesn’t want to use them).

For others I’d recommend Fedora. You see, the downside of Fedora compared to Ubuntu that I know of is that a few things that you’d expect to work OOTB actually doesn’t. For one, on freshly installed Fedora, if you use Chromium to go to youtube, you’ll find out that some videos refuse to play with an error. To make it work you’ll need to type that error in a search engine, find out that you need to add some repo and install some codecs that Fedora excluded due to them being proprietary, and then you need to understand what you’re actually doing, so you can fix your system if something gone wrong.

This is not a big deal (offhand I don’t remember having any other problem) if you recognize that overall Fedora has a big development team and good QA, and that they mostly try to keep packages up to date with upstream. But if you are absolutely new to GNU/Linux, then this is not a good first experience, you may deem GNU/Linux a “broken OS”. And this is the reason I struggle to recommend Fedora to newbies, unless it’s someone for whom I can set up the system personally.

I see lots of Software Architects, which are on the more experienced side of the spectrum using Ubuntu.

There’s many factors may be involved, it really depends. First of, nobody know everything. They may have a good grasp on GNU/Linux internals, but at the same time all they may know about other distros is their existence. Such mindset is easy to get when all/most GNU/Linux experience stems from jobs, as opposed to personal curiosity.

And then there’s also a recurring myth that unless a package you’re using is a few releases old, it’s crowded with bugs and you better not to use it (I agree it may be useful for servers, but it rarely is for desktop systems).

And then they may recognize that having most up to date packages would simplify their life as a developer at least, but they don’t consider it a good enough reason to try something new.

Or they may have heard, for example, of AUR and Archlinux Build System, but “so what? I can do well without it.”. This one is similar to blub paradox.

Or they may simply not have enough time and/or motivation to try other distros.

Or they may use it just because “everyone does”.

Many different reasons, you may get better answer asking them personally.