I love Stardew and played a bunch when it was first released.
He really had perfect timing with its release. The original developers and the rights holders for harvest moon had so badly fumbled for so long with bad releases or only in Japan releases etc. Someone was bound to show up in that space since there was a clear demand for that type of game. It also helps that he aped (heh) harvest moon from the super nintendo / game boy generation so it basically runs on a potato and no one needs to buy dedicated hardware.
“Harvest Moon but for every platform ever created” was such an obvious need it was surprising it took that long to arrive.
Just like it’s somewhat amazing to realize it took until 2009 for “digital Lego” to catch on with Minecraft.
Definitely a perfect timing situation, though with substantial risk. Considering the time the game was in development, an alternative could have showed up in the market.
However, I believe Stardew Valley’s appeal wasn’t simply of fulfilling a void in the market. It is great because there is genuine passion for the subject in the execution, and the content in the game is truly compelling for a wide audience. An amazing story.