Well one way that comes to mind for why it could be considered a burden is breaking down internal documentation into public and private, and making sure that the private one is never exposed. As much as we don’t want to imagine business constraints on some manufacturers, they could always come up with reasons.

> And if I want to abuse some piece of hardware, such as making a musical instrument out of a pile of floppy disk drives, what business is that of the manufacturer?

As an example (maybe not a fair one) we can ask Tesla why they don’t want to expose some/all APIs that Tesla owners might want access to. I expect they would bring up a thousand reasons why, maybe safety related, maybe not.

I generally agree with you though, you paid and own something, and you wish to use it as you see fit. Unfortunately it seems like what we think we own and what we actually own are in some cases two separate things.