Why use a webapp AND a local native gateway instead of just a native app? If your goal is to just not open any native win32/cocoa/etc UIs for some reason, there are existing native torrent clients with web interfaces served over http and those have been available for like a decade plus.

Webapp + native gateway also means that the torrent traffic ends up being suspended/throttled if the tab isn't foregrounded or if you close it, something you wouldn't have to deal with if the native gateway was just a native torrent client. Chrome Apps had a background privileged context that could keep running even if no tabs were open (though Google naturally discouraged this unless the app needed it), something you can't really get with a PWA currently (though Service Workers come close if you keep the tab open, I think? Maybe?)

Can we run native apps written in Rust/Go in Chromebook ?