You don't. It's a technological progress similar to one where we lost our ability to repair transistors with introduction of chips. If this doesn't work for you you should stick with the old tech, I think the Russians did something like that on their soviet era plane electronics. There are also audiophiles who don't even switch to transistor and use vacuum tubes. Also the Amish who stick to the horses and candles who choose to preserve their way of doing things and avoid the problems of electricity and powered machinery.

You will need to make a choice sometimes. Often you can't have small efficient and repairable all the time.