Let’s take a step back.
Just because a piece of software isn’t the default, isn’t actively worked on by the original developers and isn’t getting new features doesn’t render it impossible to use. I don’t understand this obsession Linux users have with desktop environments. Did Unity suddenly stop working? No, it’s continued working just fine in every release since 17.10 where it was no longer the default. I’m on 19.04 and it works perfectly.
Sure it might not get up to date fixes but you could say the same thing about a vast amount of open source software. There’s a ton of applications and libraries which are effectively in “maintenance mode” and don’t get new features and updates. Developers move on to other projects and either consider their past ones “done” or just stop caring about them. Does that mean we shouldn’t use that software? No. Open Source software doesn’t have a “sell by” or “use by” date like food.
Just because you personally may not like it, and Jack Wallen in 2011 wrote a piece about the state of play eight years ago doesn’t mean everyone should format their drives in 2019 and use some other desktop. That’s ludicrous.
The fact that I work for Canonical doesn’t actually matter for a few reasons. Firstly, before I started working for Canonical I was a massive fan of and advocate for Unity. I loved it then and still love it now. It performs better than GNOME Shell at the things I do and has all the features I need. In addition, Canonical doesn’t mandate what desktop their employees use. Indeed some employees don’t even run Ubuntu on their primary machine. There’s a slight exception for those people in the Ubuntu Desktop Team who work on making Ubuntu Desktop - you’d expect them to “drink their own champagne” on their main machine, and they probably all do. But as far as I know, nobody at Canonical ever got fired for running Arch
Unity is still in use by a massive number of people today, in 2019. In fact there are likely more people running Unity right now on Ubuntu (16.04) than there are total users of all other desktop distros combined. You may not be one of them, and that’s fine. But that doesn’t mean nobody uses it.
No. None of that is accurate to be honest. It always was open to contributions. The stack is a little complex and harder for drive-by contributions. Perhaps we should have made more effort to bring Unity to other distros, and not keep it primarily for Ubuntu. Perhaps the code should have been on GitHub rather than Launchpad. Maybe we should have removed the CLA requirement. We can speculate on all the various ways in which Unity could have been even more successful. But the fact remains, it was already very successful, no matter what news articles or thought pieces you dig up. Unity was installed on millions of machines. Not many desktops can say that. Indeed GNOME Shell couldn’t even say that until Ubuntu switched the default.