As a counterpoint, many systems that were originally implemented as native desktop applications have since been migrated to the web. The motivation for this shift is not particularly strong from a technical standpoint, but it is a practical one: deploying native applications is simply too costly.
The web finally provides a widespread standard for deploying applications inexpensively. Unfortunately, the technology used to build user interfaces for the web remains somewhat mediocre.
It’s unfortunate that history took some wrong turns with X11, Java, Flash, Silverlight, .NET, and countless other alternatives that I haven’t personally lived through.
Hopefully, someone will eventually find a way to make developing web applications comfortable and the broader community will embrace it.