i m not going to go on this island XD
as you say, its super small island.
as small it is.. i see 2 possibilities :
1 - this game is planned to be a small game, or an multi episodes game
2 - they gonna go out of the island super quick
because if they stay there ( lets pretend they dont need to eat and drink) , the game should be super boring with just 2 characters... and if some othrs characters come in the island, then it gonna turn in a big mess quickly.
no idea what is planned, but i hope the dev have some godlike plot in mind.