Pansexuality bad?

Ok so I was looking around Pinterest and minding my own business and I saw this pin joking about how bisexual people are half straight and half gay. In the comment section there were people arguing about how being bi doesn’t mean you only like 2 genders but it actually means you’re attracted to all people regardless of their gender. But then people were arguing about how that’s what pansexuality. This kept going on for a while and this is what I got from both sides.
-pansexuality has transphobic and biphobic roots
-bisexuality is not limited to two genders but can mean liking multiple genders

-labels change as time changes so bisexuality being only two genders and pansexuality being multiple genders is valid
-people not acknowledging that pansexuality as valid is panphobic

I‘m interested in hearing what you guys have to say about this conversation and what your takes in it are.