From reading this that’s not the whole story. Someone working at canonical successfully made a version of snap that could use alternative stores, but the default version does not allow it
And honestly at the point of installing that modified version you may as well just install a different package manager anyway
Help! My family's starving and I only know how to play 1947 West Siberia Economic simulator... (lemmy.ca)
Canonical lifts lid on more Ubuntu Core Desktop details (www.theregister.com)