I am not sure, but I think all systems are prone to this. I had an Xbox 360 that was working great, I stored it well enough in its original box for more than 10 years, I turned it on, and somehow it had the RRoD. My original Xbox had issues as well, I had it for more than 12 years stored in my room, I turned it on, it was working and reading discs, I bought an SSD to mod it, and then DVD drive failed on me. I have heard that Wii U systems randomly die if they weren't turned on for a at least a few years, at least I have heard this a few years ago.
Someone who is an expert in physics or electronics might know the reason why this happens. It could be worn out solder joint, it could be some electronic components or motherboards dying of age, or something else entirely. Capacitors usually don't leak if the system wasn't used.