Of course in practice, both your Registrar and Nameserver will be the same as the Homeserver, which in turn is most likely would be the default server of the developer of App you downloaded and possibly paying for... So really not very different from just buying a domain from a hosting provider... But you can move from their to a better more sovereign place... Or not!

Which is by the way why Mlkut Homeservers and the rest of the protocol should support ICANN domains, if some people are hell bent on not having self sovereignity ever, might as well get a nice subdomain? But maybe encouraging this ends up being a big mistake.