@manithree: I suspect that RPi is more fragile to electric shocks or overvoltage damage since it has a lot more components, of which many are sensitive to high voltages. The OSPi board has a relatively small number of components and many of them (like the shift register) can take a lot of abuse.
I damaged my first RPi by simply connecting a digital output pin to GND. That fried the power circuit instantly 🙁