It's like arguing the moon and sun are the same size because they look the same size when looking at the sky. A hamburger with added plastic is essentially a hamburger. A hamburger made out of plastic that resembles beef is not.
I don't understand how you can interpret "pure means not adding in stuff to water it down" as "everything that's vaguely similar is the same", because from my perspective that's exactly what the parent comment I responded to is doing
