More specifically, Google is forbidden to replace IETF-approved and wide-acknowledged API with its own proprietary substitute without being accused of being evil.

Seems to be fair enough for me, just in case anyone cares.

Not really, but in this case, they have failed to give any justification for not following a standard that industry giants like Apple follow and which Microsoft is close to implementing on Windows Phone. Perhaps there is a technical reason, but Google not being open about it makes people assume the worst.

It's also in contrast with some of their own previous behavior. When they saw opportunities to make things faster/better, they were comfortable breaking standards (or, well, making new tech that might stand as a standard one day and asking people to let go of older standards). One example: SPDY. Another: go. Additionally, there's a whole bunch of examples from chrome where they broke conventions for user experience and drew people's ire, but in all cases they defended these decisions with well thought out (if controversial) arguments.

Where's the argument against CalDAV? (I'm not saying it doesn't exist, I'm just surprised to not have seen anything from them)