Desktop users who last used, and liked, Ubuntu during the pre-Unity/pre-GNOME-3/pre-Wayland era (before 2011 or so) may not like it so much these days.
It's a very different default experience now.
While I have fond memories of the earlier releases of Ubuntu, the more modern releases have been pretty much unusable for me any time I've tried them, unless I redo the default desktop environment with something sensible. Snap certainly hasn't helped the overall usability, either. Having to make so many changes pretty much defeats the purpose of using a distro in the first place.
I've also helped several non-technical and semi-technical macOS and/or Windows users who've wanted to try Linux. The ones who wanted to try Ubuntu first ended up much happier when I eventually introduced them to KDE running on X.
GDP seems like a very questionable, and likely misleading, measure to me, even for Western nations.
For example, Canada's inflation-adjusted per-capita GDP has supposedly increased over time, yet for many Canadians, the standard of living is now noticeably lower than it was (or would have likely been) two or three decades ago.
In terms of production, Canadian businesses and governments generally don't seem to have become more capable and productive, and actually seem to struggle now with the sorts of fundamental work that they managed to pull off in the past. Many common services and products are noticeably worse now than in the past, in terms of cost, quality, reliability, delivery time, and so forth.
It's quite simple: many people had atrocious experiences with systemd.
Systemd ruined Debian for me, for example.
I'd been using Debian testing for years and years, on multiple systems. Despite its name, I'd always found Debian testing to be more reliable than the stable releases of other major distros.
When performing updates and upgrades during those many years of using Debian testing, I had only ever experienced trivial issues that I could easily resolve, usually just on my own with a few minutes of investigation.
Then systemd was forced onto Debian's users.
As soon as it ended up on one of my systems, the problems started. That very first update left my computer unable to boot. That was the first time in over a decade of using Debian that that'd happened. I also remember it taking far too long to diagnose and resolve whatever that initial problem was.
Subsequent updates involving systemd just caused me more and more problems. They usually weren't minor issues, either. They'd significantly impact the usability of my installation.
To make matters worse, I, as a user, didn't see systemd even bringing me any benefits.
Eventually, I lost my ability to trust in Debian and its reliability, even for Debian stable once systemd eventually made it there.
Now I completely avoid Debian and other systemd-using Linux distros whenever I can.
It's a very different default experience now.
While I have fond memories of the earlier releases of Ubuntu, the more modern releases have been pretty much unusable for me any time I've tried them, unless I redo the default desktop environment with something sensible. Snap certainly hasn't helped the overall usability, either. Having to make so many changes pretty much defeats the purpose of using a distro in the first place.
I've also helped several non-technical and semi-technical macOS and/or Windows users who've wanted to try Linux. The ones who wanted to try Ubuntu first ended up much happier when I eventually introduced them to KDE running on X.