There are many customers that care about owning their own data. Despite what you might think, there are lots of companies that do not trust sending their data to the cloud. In addition, there are lots of companies and individuals that have all their data local, for a variety of reasons (often security) and primarily use desktop applications to work with that data. The "vast majority" may never care, but the compliment is still a very sizable market.
I would love to see another way to deploy local software, aside from building dedicated Windows and MacOS apps. There are efforts in the Docker container world to provide smaller deployment frameworks. There are efforts in the WASM world to replace containers with WASM deployment (which works well in browser, BTW).