Alternate idiom for “Let them eat cake” [closed]
Unfortunately that phrase habitually comes to mind when I want to be chidingly sarcastic towards someone who is out of touch with the reality of a subject, as it's not the right idiom.
This is an obscure reference – too obscure I think for general use, but a good example – the humorous quip from the movie Heathers (1988), where the reply to a long idealistic diatribe is: “Call me when the shuttle lands.” (https://www.youtube.com/watch?v=bZx9DhBlB0w)
I don't think that even makes sense logically, but his position is well understood nevertheless.
Other examples:
“I think war should just be outlawed.” [said in self-righteous definitive tone by a 17 year old] - - A general idiomatic sardonic reply: ____________________.
“I don't understand why there are poor people; they should all just get jobs.” [said by annoyed wealthy Beverly Hills woman] - - Reply: ____________________.
etc.
Pithy, sublime, snarky, or what have you. Preferably something with some teeth that's instantly understood to be sarcastic, or ironic. I'm thinking of a movie set-piece where your favorite decidedly snobbish upper class British character has a deadly quip for just such an occasion.
Solution 1:
You could use is that so?
That is what you say, but I do not believe you. (No rising question intonation. Slightly rude.) Mary: You are making a mess of this. Alice: Is that so?
Alternatively, is that a fact?
Also, is that so? Phrases indicating that one is following what another person is saying. These expressions, which require no reply, can be used either straightforwardly, as in You mean you've flown to Paris three times just this month? Is that a fact? or sarcastically, expressing disbelief or contempt, as in Just wait, I'll be promoted over you before the year is out.-Oh yeah, is that so? [Late 1800s]
(emphasis mine)
Another possibility is good luck with that:
statement used to express doubt in the future success of someone's plan.
Solution 2:
Consider,
Don't hold your breath
Fig. Do not stop breathing waiting for something to happen that won't happen. (Meaning that it will take longer for it to happen than you can possibly hold your breath.) Sally: Someone said that gasoline prices would go down. Bob: Oh, yeah? Don't hold your breath. McGraw-Hill Dictionary of American Idioms and Phrasal Verbs
We should be so lucky!
You should be so lucky!
(informal) Something that you say in order to tell someone that what they want is not likely to happen Cambridge Idioms Dictionary
In your dreams!
(humorous) Something that you say to someone who has just told you about something they are hoping for, in order to show that you do not believe it will happen Cambridge Idioms Dictionary