Prime factorization question (Tips tricks and shortcuts)

Hi so for this question from Tips Tricks and Shortcuts Session 3, why do we count the 3s in 63 and 69? Like shouldn’t the number also have 2 as a factor since that too is a factor of 6?

I mean you can do that, but you will notice that counting 2 does not change the answer
Because 3 is the limiting factor (is fewer in numbers), whereas 2 is abundant
64 alone is 2^6

Simply counting the 3s can give you the answer, that’s why this is a shortcut