It is worse in that Hangouts does not make false claims about its security, so people who use it know that they are using it for features provided by the kind of security it provides (only between the user and Google), like searching chat history across devices.

iMessage can also only guarantee security between the user and Apple due to Apple distributing the public keys (but to a lesser extent because it uses worse crypto), but it does not provide the usability features like searching full chat history across devices that Hangouts does.