From what I remember poking around at Hansa that's not true. Each vendor / user had a public key associated with their account. All text communication through the website was supposed to be with GPG encrypted text secured by private keys unavailable to website.
So law enforcement has lots of encrypted text along with some clear text from users not informed enough to follow any kind of opsec.
I think you are probably partially correct in the sense that a company as large as Google is not comprised of one single personality. The decision making voices in Google could well run the spectrum from those advocating a moral line in the sand all the way to those bottom liners that were convinced that an action like this could well have enough PR upside to offset any potential losses in the Chinese market.
So law enforcement has lots of encrypted text along with some clear text from users not informed enough to follow any kind of opsec.