There's a lot going on here, and it depends on the context where you're encountering it but. . .
I think 'between you and I' is a special case because kids get corrected for using me as a subject pronoun ('you and me are going the park') because it's a natural grammar 'mistake' that kids make that is easy to recognize as a mistake. So people internalize that 'You and I' is correct and 'you and me' is wrong, and the 'I' construction ofteninstinctively *sounds* more 'correct' whether or not you have a great grasp on the prescriptive grammar.
Also, I'm not a linguist but I don't think there actually is a difference of meaning/clarity between subject and object pronouns in English so it truly doesn't matter. (EtA whereas if I am understanding this correctly, in a case based language system, the form of the pronoun you use tells you things about meaning -- in English, the prepositions + sentence structure do that work.)
no subject
I think 'between you and I' is a special case because kids get corrected for using me as a subject pronoun ('you and me are going the park') because it's a natural grammar 'mistake' that kids make that is easy to recognize as a mistake. So people internalize that 'You and I' is correct and 'you and me' is wrong, and the 'I' construction ofteninstinctively *sounds* more 'correct' whether or not you have a great grasp on the prescriptive grammar.
Also, I'm not a linguist but I don't think there actually is a difference of meaning/clarity between subject and object pronouns in English so it truly doesn't matter. (EtA whereas if I am understanding this correctly, in a case based language system, the form of the pronoun you use tells you things about meaning -- in English, the prepositions + sentence structure do that work.)