If you mean HTTPs is great to check if it's coming from the right server (identity/authority) then well, see how well the CA system works and how weak certificates really are (e.g. "Ron was wrong, Whit is right"). You can work around that by doing certificate pinning (see google chrome for example) and stuff like that, but in that case I'd already be better off signing the payload and sending that as part of the response.
The scientific institutes of germany worked around all the CA headaches by becoming an intermediate CA (see who signed https://www.pki.dfn.de/ ). I'd just expect more intermediate CAs popping up as a result of HTTPs only which will weaken HTTPs even more.
(And yes, I'm using https everywhere and would enable https for just about every site, except e.g. for linux iso downloads and alike)