If building for multiple targets, some of them might not support PWA. It would be great to have an option to turn off the functionality

What targets are you referring to? Why would this option be helpful, what problem did you encounter that it would solve? Or what improvement does it bring?

AFAIK, if a plattform / browser doesn't support Service Workers, it's simply skipped.

I am currently developing the following app for multiple targets: https://collect-app.com/

Especially for iOS and macOS I distribute the built HTML/CSS/JS inside of the app package I put on the respective app stores. WKWebView (the OS's native web view) is used and it supports PWA. But in this scenario it doesn't make much sense, since the access is instant and always "online" (at least as seen from the app itself). Therefore a service-worker is contra productive, because this extra step is not required.

For Windows and web browsers instead PWA makes sense. See http://desktop.collect-app.com/ and https://mobile.collect-app.com/ as examples (work in progress).

After looking closer at it, I have to agree, that by just not registering the service-worker the whole PWA functionality can be avoided. I would still like to avoid this step via config instead of post processing and deleting the superfluous files. But indeed this feature is not very urgent.

when npm add @vue/cli-plugin-pwa into dependencies, but dont configure it in vue.config.js( or config like pwa: {})
finally, the build bundle would build serviceWorker.js/robots.txt/manifest.json, these files should avoid building
i dont register service-worker in main.js, and built files would include serviceworker files
@LinusBorg

I need the same functionality for same reason. some of my build targets do not need a service worker(because they are in a local server anyway), I'm afraid it can cause buggy behaviour. I dont want to have it, i dont want to think about it. This is not just me : https://stackoverflow.com/questions/52800904/disable-pwa-plugin-in-vue-cli-3

I think this makes sense. I'll do make a PR.

temporary workaround

https://stackoverflow.com/a/48188540

config.plugins.delete('pwa');
config.plugins.delete('workbox');