There are other benefits: A PCB design can be shared so that others can fabricate it themselves. (Or modify it if they wish). A PCB design will likely have a schematic, too, which can be studied.

I'd also bet that PCB projects are more likely to inspire better PCB projects. -- Or at least, the domain I've tried my hand at has been PCBs for custom mechanical keyboards.

e.g. I've seen boards inspired by https://github.com/hsgw/plaid such as https://github.com/coseyfannitutti/discipline or https://github.com/rtitmuss/torn and I think there are several popular split keyboard designs which basically descend from https://github.com/MakotoKurauchi/helix