Well it depends really.
People have been concatenating all their files down to once for quite some time, so I don’t think it’s too bad.
Webpack2 also bring incremental builds via module replacement. So say Page1 changes, only the contents of Page1 will be update, and not the whole build
Minified and GZIP, the file size won’t be anything too crazy. Plus, as angular2/ionic2 progress, we can expect to see file size drop a lot
Again, it’s the same logic in an ionic 1 app. Even if a user didn’t go to a particular state, all the controllers and templates for that state were loaded upfront, so not much has changed here. Plus both projects are still in beta, so there’s no reason to think that this could change.