Turkeys voting for Christmas is an English idiom used as a metaphor for a situation in which a choice made is clearly against one's self-interest. In the United Kingdom, turkeys are commonly eaten as part of the English Christmas dinner. To support or participate in something that will ultimately harm yourself, like turkeys voting to be eaten for Christmas dinner; it describes a self-defeating decision or action, often used in politics or business when people back policies detrimental to their own interests.
It signifies a choice that is clearly against one's own best interests.
It's used for situations where individuals unknowingly support something that leads to their own downfall，
Xmas turkey
The phrase stems from the tradition of eating turkey as a Christmas meal in the UK. It was popularized in British politics, notably by Prime Minister James Callaghan in 1979, to describe parties supporting measures against themselves.
e.g. for many of the MAGAs
"Voting for that tax cut that benefits only the rich is like turkeys voting for Christmas".
"Agreeing to the new terms without reading them? That's like turkeys voting for Christmas!".
