Honestly if you want to go this lightweight I think desktop PWAs are better suited, they’ve been around for 4+ years but are horribly underutilized
For example on macOS, Electron plugs into the global menubar, making it easy for web app devs to give their Mac users native menus instead of falling back to a redundant in-app menubar. Nearly all electron apps on macOS take advantage of this feature, and if they migrated to PWAs they’d lose it.
PWAs also lack fine grained control over window chrome which puts them in an awkward twilight zone between browser window and desktop integrated web app.
Just because you can wrap some web frontend framework around some libraries and take some fancy screenshots of your landing page doesn't make the software good.