As a dev: for all their flaws, web apps are easier to distribute, portable, and have a lot of support in frameworks. They also require little infrastructure in most cases.

As a user: web apps run without installing anything, are mostly portable between my browsers of choice, and run in a sandbox to protect my computer.

Probably 90% of my needs can be served by a web app if it is well designed. If I can't have a web app, I will look for a flatpak version and failing that I will look for it in my distro.