My favourite version is as follows:
Bi: I like strawberry, chocolate and mint ice cream
Pan: I like ice cream
The salient point is that bisexuals will discriminate based on gender, they 'see' gender in their preferences, so to speak. To a pansexual, gender is irrelevant.
I'm bisexual, I see men as a whole, my boyfriend included, differently to women and non-binary people. You may end up with the same results, but not getting there the same way!
And as an aside, within the bi community, bisexuality is attraction to two or more genders, so, yep, some of us do like non-binary people!