Adventure Island is an almost prototypical platformer. Its graphics are cartoonish, its music is catchy, and its action is kinetic and non-stop. While the game is challenging, it also is light-hearted enough that even after multiple defeats, the player might want to try just one more time. The game play is intuitive enough, but is spiced up by the inclusion of various power-ups. Along with differences in gameplay, the game also takes the player to a variety of different worlds, each thematically different. It also spawned a host of sequels, each keeping the basic game mechanics while expanding on the basics.
Most of what could be said about Adventure Island could be said about Super Mario Brothers, the most influential platform game of all time. If you were to find someone who have lived in a video-game free cave for the past thirty years and had them sit down and play both games, I don't know which one they would prefer. In production values and gameplay, they are both great platformers. But a generation of children grew up playing Super Mario Brothers because it was bundled with the NES, and it got enough momentum that it infiltrated popular culture and its tropes and themes and music are familiar even to people who never played it. Adventure Island, and its sequels, while well-regarded by video game enthusiasts and hobbyists, is not well known in a general sense.
It can probably never be determined whether this was because some flaw in Adventure Island itself (too difficult? not enough diversity? graphics too silly?) or just the circumstances of it competing for public recognition against the juggernaut that was Super Mario Brothers.