You are basically StarOcean's evil counterpart. Mind you, Star Ocean is evil as well.
All Nintendo handhelds prior to the 3DS had battery life of at least eight hours.
I had a Gameboy and Gameboy Advance, I don't remember the battery life being that long... That said, having to constantly buy batteries was the worst thing ever, so I'll gladly take a smaller battery life for something I can charge with a charger. I just wished the Switch charger was longer, so I could play it comfortably on the couch while it's charging.
The fact that I can't remember the battery life of the Gameboy makes it all the more irrelevant to me. Who plays for 8 hours straight anyway?
"The strong do what they can and the weak suffer what they must" - Thoukydides