I would argue that in this architecture, you're _not_ hosting the services, Amazon is. Therefore it's not self-hosting.

The phrase "hosting the domain" is also subject to the same conclusion. Registering a domain for use by a 3rd party service provider is not the same as "hosting" the DNS. To actually host DNS requires running an authoritative DNS server. Self-hosting DNS would imply running this service yourself, not using a 3rd party DNS service provider.