Your deduction, that not everybody's cup of tea means not to everyone's liking, is absolutely correct. The indefinite pronoun 'everyone' is a singular pronoun. I have the following sentence:
An example would be it flew over everyone's heads, or it flew over everyone's head. In fact, to catch someone's eye is an idiom, not eyes. the question is not about everyone being singular or plural. What would be correct in this case and why?
The possessive form is everyone's (the form everyones' is incorrect).example: Would the noun following everyone's be plural? Are the words everyone and everybody singular or plural? Joe got everyone's attention and started to speak.
The expression commonly used in both the affirmative and negative. Everyone who is coming will receive a gift. May i have everyone's attention,. Unless of course you’re a buddhist or a cat, in which case everyone has multiple lives and both would be correct, depending on context.
There is a comprehensive article on the topic on grammar girl: The possessive of everyone is everyone's, in the same way the possessive of everybody is everybody's. Should it be everyone's, everyones' or everyones? There are actually two issues concerning this topic: