Yup, the thing is the price difference between the humongous flash (do they even do EEPROM anymore?) and the "appropriate" one is less than the overhead of designing/making/handling different sizes. And the bigger the chip the more sectors for wear leveling and you can tolerate lower total write counts on the chip.

Thus we end up with circuits designed to feed the reinforced concrete outhouse in the center. And they're unrepairable because the troubleshooting cost is more than the replacement cost.