I think this is not about whether it’s possible to do hot reloading with Angular or not — of course it’s possible. You can also make a regular JS/jQuery app hot-reloadable by leveraging the raw Hot Module Replacement API.
But the question is whether it’s readily available and easy to use or not.
With React, you enable a flag in webpack-dev-server and configure some Babel transforms, and it’s done (although that’s quite some work already). So I feel that for a new framework to compete, it should be as easy or easier to set up hot reloading.