You can still buy the Gros Michel banana nowadays. It's not extinct, but is a rare and expensive speciality, rather than the common type of banana we see on the shelves like it used to be.

$37 USD per banana, on this particular site

If climate change makes growing Arabica coffee commercially non-viable at scale and all the growers move to hardier alternatives, then Arabica will still exist - absolutely - but instead of being the coffee you can drink every day it will also become a rare and expensive speciality, just like the banana.