I don't expect access to something running a minimal SoC with code burned to its ROM. I do expect it for something with a general OS that runs arbitrary code.
This can get tricky with modern devices. For example, pretty much every router runs some version of linux. Most do not give you root unless you flash your own firmware.
Also, a lot of IoT devices happen to run minimal but functional operating systems. I personally think whether something counts as "general purpose" or not is a gray area and depends greatly on the manufacturer's intent, and it's pretty clear that these manufacturers do not intend for users to run arbitrary software on the devices they make.
I disagree with that; in my mind the distinction is not whether the manufacturer wants me to to run arbitrary code, but whether they expect/intend themselves to be able to run arbitrary code after the device is shipped. So ex. a dumb digital watch that just has time/date/alarm/stopwatch functions is fine because once it's sold the manufacturer never expects to update its code (and said code is probably on actual read-only ROM), but an Apple Watch is intended to run arbitrary code - just that Apple locks down that ability to code that they allow, which I do object to even though Apple never intended to let users run their own code at will.
Most of them are a little more than minimal, almost all of the ones I've seen are running full buildroot Linux with tons of shell scripts gluing stuff together and the main app in C++.
I don't expect access to something running a minimal SoC with code burned to its ROM. I do expect it for something with a general OS that runs arbitrary code.
This can get tricky with modern devices. For example, pretty much every router runs some version of linux. Most do not give you root unless you flash your own firmware.