It is about discerning FALSE PROPHETS, it does not have universal application. You cannot make it say something it does not, that is reading into the text (eisegesis) not reading OUT of the text (exegesis).
There are other verses that discuss your point but ‘by their fruits’ isn’t one of them.
Part of what is wrong with ‘feel good Christianity’ is a definitive lack of proper exegesis. Sad really.
BTW, theology is my job (or at least one of them).