You really don’t?!!!
Not everyone does. Not knowing him does not make you less musically inclined, does not make your musical taste inferior to others, does not make a generation guilty of some kind of cultural treason.
Why not make this a grand opportunity to introduce Paul McCartney’s work to those who don’t know him? I’m sure some remember the grandiosity of listening to the Beatles for the first time. You can impart that gift to someone instead of calling them an ignorant ignoramus.
If you love something you share it, not bash others because they haven’t heard of it.