I suspect its mostly a change in the types of applications being written. Most of the trends today are about interconnected sharing of data or aggregating data

I suspect its mostly a change in the types of applications being written. Most of the trends today are about interconnected sharing of data or aggregating data from across sources, internet applications for want of a better term. There aren't many new commercial applications being developed because its inherently a single user experience creating or editing data locally. They are still being created in the open source community however, non linear video editors have come quite a way in the last few years as have some interesting learning tools like Anki and IDE stuff like VSCode, I have added 10 or 15 applications to my list in the past years for all sorts like cartoon drawing. But the desktop isn't perceived as profitable for a new application and a lot of the tools have ended up with obnoxious DRM and charging schemes like Adobe. It is just not a hot area of innovation and its not being pursued. I have also found that as a consequence a lot of modern languages are very light on GUI support if at all. Rust, Go etc etc do not have robust GUIs of their own and you end up bridging across to other languages and working in odd ways or with very bare bones implementations like fyne. On Windows at least your best bet for a GUI remains either C/C++ with Visual Studio or .net and the other choices are a long way behind. We are seeing the rise of the web interface via Node and such as a result, its cross platform because its just embedding a web server as a control but its providing a local application but as people often point out they don't run well and they lack native feel and performance and its not a great experience. There are technical issues here too but I think its really more that few people are looking at these types of applications and a few big companies maintain most of the big commercial applications and buy up anything new to include in their suite.