Been a while since I’ve had Inca Kola, but it did remind me of Juicy Fruit, a banana/gum flavor.
I might be misremembering the citrus component of bubblegum now that I think back, and it could be an ester flavor (a typical artificial banana/fruit flavor) instead… Fresca has ester components as well, which might be the contributing factor to “A&W/Fresca = bubblegum” rather than the citrus component.
Been too long since I had that flavor chemistry lab… 