Missed opportunity indeed
Minecraft was the case of a missed opportunity by many people and companies and a complete lucky break for the developer, Markus Persson.
The original idea for the game was developed by Zachtronics Industries' Zachary Barth and called Infiniminer, but after the source code leaked he stopped developing it. Persson picked up the idea and ran with it, making Minecraft.
Lego should have made the game years ago, but I imagine like many older manufacturers it was worried about cutting into its real-world brick selling business. Microsoft missed the boat with Minecraft too by buying too late. Its only hope lies in it releasing a sequel somewhere down the line, which won't have the same heart as this version.
Most of the people who were going to buy Minecraft have done so already. There is no way Microsoft will make back that $2.5 billion.