It’s an English language idiom that always trips me up. Here’s another example: https://englishidiomsblog.blogspot.com/2010/10/tell-us-how-y...
The idiom is someone says “tell us how you really feel” (which he’s rephrased here) to express (I think) that one’s expressed opinion is far too dramatic in its opposition of some thing. It’s meant to be read ironically.