Batteries wired in series increase the voltage provided. The example in the OP us just a battery whose LEDs run at anything from 1.5V to 6V and accepts both AA and AAA batteries. It’s not a foil to planned obsolescence, it’s just smart design. It could still be made with the same design, but purposely use LEDs that die sooner, in which case it’s smart design and planned obsolescence.
Batteries wired in series increase the voltage provided. The example in the OP us just a battery whose LEDs run at anything from 1.5V to 6V and accepts both AA and AAA batteries. It’s not a foil to planned obsolescence, it’s just smart design. It could still be made with the same design, but purposely use LEDs that die sooner, in which case it’s smart design and planned obsolescence.