I'm sorry to disagree, but you're wrong.
We can and should ask to have the cake and eat it too. In the same way that a public figure foregoes the right of privacy in exchange for the privilege of fame, a diplomat has foregone the right to privacy in exchange for the privilege of acting as a representitive face of the government they hail from. If that isn't a sacrifice they feel comfortable to make for the term of their service, they should not be acting as an ambassador.
A government is not a person. It should not hold the expectation that it will be privy to the rights granted to a person. It is an agency which exists for the sole purpose of serving the common good of the people who exist within it. If the people who exist within it doubt that it is in fact, serving their common good, there can be no remedy to alleviate this doubt except for the citizens to be able to examine its actions in depth. An implicitly sustained state motto of "Just Trust Me" is foolish and encourages corruption, abuses of the individual's rights and improper and unnecessary curtailing of the rights granted to those citizens. In short: If a government is granted the right to "tell and not show", there can be no way to safeguard against the worst evils of government. Knowledge is the power that allows citizens to regulate their government.
Even for regular people, there is an understanding that our privacy exists -only- as far as is reasonable without risking the rights, property or health of others. You do not reasonably expect an officer of the law to not examine you when he pulls you over for swerving simply because "I should have the right to my privacy". You accept that his job requires him to examine your credentials and condition for the welfare of other drivers. Even the smallest action of government will impact all three of the things I have previously mentioned. If we would not tolerate extending a person's right to freedom over those facets of the common good, then we certainly shouldn't be cutting government any breaks in that respect either.
And I unfortunately have to disagree with the idea that Julian Assange was out of his rights to display emails he had gained access to. While I like to think my own emails are private, I'm perfectly aware that any number of unsolicited entities such as for instance, my government, have the ability to intercept and put to use anything I am sending. There was never any form of guarantee that it would actually stay private and if I thought there was, that was my mistake for assuming a right that was never actually stated. Email is not the Postal Service despite what people think.
The fact is that Paypal has taken a stand, just like what you've said. And that's the problem. When we allow corporations to become vehicles for political views, we are encouraging financial entities considerably more powerful than the individual to influence democractic systems. The idea of democratic governments has always been that we (the individual) are ants that individually have very little power but collectively can move boulders. A beautiful idea, if not always perfect. How then do we compete when corporations, who have the power to weigh upon the system like bears, begin to push the boulder in the directions they like? Should we, the ants, encourage the bear to push around government as best suits them? If we let, or worse, encourage corporations to 'take a stand' on political matters, especially those outside of their immediate sphere, how long before we have corporations using their collective clout to publicly control or take ownership of governments that depend on their favor? Maybe you should be asking yourself why Paypal making -any- political decision is a good thing, 'right' or 'wrong'.
