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To do a 5V USB-C charger from scratch you only have to do roughly this.

USB-2.0 is even simpler, just connect power and ground, and short the data pins.

The data pin short, btw, is so the connected device doesn't try to "connect" to the power port. It detects the short (in that it simply receives every data packet it tries to send) and hence knows that it's connected to a charging port.

Yes, PCB manufacturing from scratch is a bit pricey but for something this simple it would, I think, still be in the single digits per board if you buy a small quantity. The main reason against doing that is that the off-the-shelf solution is satisfactory.

Apple products require a signal on the data pins and without it they won't charge which I discovered when I put in solar powered USB ports in our offices and den during our remodel. It was easy to remedy but a pain to have to do so. I guess that's their way of making sure you use their chargers!

Huh. Yes the D+ and D- lines must be held at 2.7V to support 12W charging (at least for USB 2.0).electronics.stackexchange.com/questions/ ... ow-are-the-d-and-d-lines-configured

Not hard; just take high precision pair of 39k and 33k resistors between 5V and ground. Or 43.2k and 49.9k, ideally.