Canconda’s original comment did not have the wiki link which is why I replied. Honestly, dropping 23 possible birthday pairs to reach >50% probability is still not intuitive to me.
Of my OG friend group of ~12 there are two matching birthday pairs. One coincidental and one pair of twins which don’t count.
I can see it kinda. At the same time you are reducing the unique dates and increasing the people you could match with.