In any real-world application, the processor chip is likely to be more reliable than the peripherals, eg. batteries, LCD screens, sensors, switches, cables, connectors and so on. The reason I say that is it doesn't have any moving parts. Or chemical reactions (like batteries).
I would be surprised if Atmel survives by selling to hobbyists alone. It's a pretty tiny market. How many friends do you know that play with microprocessors?
Possible, but just claiming that without bringing evidence does not weight too much.
How much evidence do you want? Do you think Apple survives by selling its products to developers alone? Or Microsoft?