PlayCanvas WebVR is a little broken at the moment so I wouldn’t consider it for VR work at the moment.
To answer your question directly. PlayCanvas is a browser WebGL engine so it uses WebVR for it’s VR capabilities. If you wanted to release a PlayCanvas ‘app’ to any of the stores (PC, Android, iOS, etc), you would have to compile/build it in a HTML5 ‘wrapper’ like https://cocoon.io/.
However, I don’t know if that works for the Oculus Go App store.
All that said, if you are planning to release a VR game as native, I would use something like Unity or Unreal, with the former being relatively easy to do as there are existing project templates to use that can be published for all the major VR platforms. You also get the added performance boost as you are running native rather than via a ‘browser’.
WebVR is best used when you want someone to be able to ‘instantly’ access the experience without having to install an app from the store (it also means you don’t have to submit to the store). It works well with Google cardboard and GearVR.