On the other side of the equation, two items that take a heavy toll on modern electronics are moisture and thermal cycling. Keeping the WXR on keeps it dry, and turning it on when cold soaked at altitude will cause the solder joints to crack much more so than when turned on leaving the gate. Remember the old tube TV's and even the news ones. Who's TV never dies? ans. the guy that leaves it on 24x7. When does it die, not when it's on, but when it is turned. How many times does an aircraft taxi to the gate OK, and break when fired up from cold for another flight.
That philosophy was told to me after the introduction of B757/767 to our fleet; especially in winter. It cost a bit in GPU time though. I guess the tree huggers would frown upon a GPU being on for 6 hours every evening; so why not an electronics battery cart? Why have a diesel noisy GPU chugging away. Where's TESLA when you need them? That's an idea. Think of the worldwide need for battery carts instead of GPU's. All this guff about shutting down APU's and plugging in GPU's. OK many stands have plug-in mains voltage, but not remote parking or non-stand airports of which there are many.
If your company SOP says turn it on and leave it on because you may forget (or be to stupid) to turn it on when you need it,
Wouldn't it be nice, just once, to be treated as intelligent and told why a strange sounding SOP is introduced? Understanding why we do something not only educates and informs, it helps one to remember and appreciate why it is being done; rather than just complaining that some dimwit has decreed it.