> "we don't do that here"
As a newcomer to wherever, given this treatment I'd feel excluded and somewhat upset. Who is "we"? Am I dealing with a homogeneous group and this person is speaking for all of them? Why don't they do "that"? Am I the only one that's different?
> preferred way to say no: “that doesn’t work for me.”
That... doesn't work for me? If you want to say no, just say no. If you want to say more, I'd be very grateful if you could tell me why not.
I'm sure the magic phrases have made the author's professional career easier. Also I'm sure they made life worse for other people.