IMO It's not unlike all other "dev" tools we use at all. There are tons of free and open tools that usually lag a bit behind the paid versions. People pay for jetbrains, for mac os, and even to search the web (google ads).
You have very powerful open weight models, they are not the cutting edge. Even those you can't really run locally, so you'd have to pay a 3rd party to run it.
Also the competition is awesome to see, these companies are all trying hard to get customers and build the best model and driving prices down, and giving you options. No one company has all of the power, its great to see capitalism working.
I am no expert, but I have to imagine it would be quite hard to learn electronic repair without learning some basic circuits.
I've learned a decent amount with some electronics adjacent hobbies, like 3d printing, diy sim racing stuff, mechanical keyboards. Mainly just copying things other people build. Enough that recently I was able to diagnose a broken transformer in an electronic theater chair power supply.