Didn't Macs have trouble booting if the clock is wrong? IIRC because from the system's point of view some cryptographic certificate's validity is in the future...
Yeah, that's the problem you want to make sure users don't face every time they power on their device.
Guessing: Perhaps, after Fukushima, Japan, like Germany has become very conscious about allowing people to completely shut off their devices when they are not using them?
I do remember German computer mags being very concerned with standby/operating power usage already like 15-20 years ago for things like home routers.
Button cell clock batteries have been a thing in most computers since at least the 1980s (including in every previous Playstation console that has an internal clock, PS2 and up), so it's not that unusual to see one in the PS5, and I don't think influenced by anything recent.
