I can understand the feedback and I agree if you are building a product, you want to make it easy to use and intuitive for the majority. In my opinion, as a government you have an obligation to create processes differently though. You should provide and focus on a flow that is 100% in your/the citizens control with the messaging to match.

So in your email example, I think the governments messaging must be neutrally on email (and arguably the government should provide free Email accounts to citizens), but they could add convenience buttons to open GMail or similar.

But I recognize my opinion is probably an outlier, especially on hackernews. I can see your point as well and taken with an open mind :).