I understood what was the issue. The problem was related to the Android emulator and in particular the development build I was creating.

The development build to be opened and run in the proper way needs that the development client is up, this can be done by simply

npx expo start

If you don't use load the development client the emulator will not be able to load the build. This will not happen only on emulators but also on real devices with the same development build.

The only expo builds you can run without loading up the client are the production builds, which are the builds that will be used and submitted to the stores.