To unpack the question, are the dialogues decently, loosely, very loosely, or not at all following actual historical meetings in accordance with the context plato provides in his works, and would any of the speeches or lines of argument be familiar to an Athenian audience (especially ones made not by more antagonistic interlocutors)?
If I could add a question: Was Plato known for going out and engaging in dialectic in a similiar way to how he portrays Socrates? In the dialogues Socrates meets all sort of people, friends and foes, and discusses with them. But from reading Platos history I always get the impression that he spent most of his time writing or educating/discussing philosophy with his circle of students and friends. Plato appears much more as a academic who's interested in writing and discussing with the great minds of his time, while Socrates seems a bit more like a tramp, who enjoys casually roaming the city and discussing with whomever he comes across. Is that who they were or who they were perceived as?
PS. Maybe it's not appropriate to say that Socrates is a tramp but I don't know what other word to use.