Portable hand held medical devices - such as Glucometers. They fall into both categories. They are medical devices, who's "bad" software could cause a user to give them selves too much insulin (hypoglycemia -> pass out -> seizure -> death), or too little insulin (Hyperglycaemia -> stupor -> coma -> death).
That would be a good reason for the user not to change the software in this device. However, that does not mean he should be stopped.
After all, the user could also change the circuitry in the device, if he is inclined to do so. That too could make it give bad readings. So what? We do not need a nanny state stopping people from going out of their way to take risks. Warning them is enough.
They are marketted, and purchased by end consumers (Amazon shows 115 results in their search), and I would think that would make them fall into the "User Products".
These are indeed User Products, and the user who buys them should have control over what they do.
I hope that you can respect my choice - and not try to convince me or others that your choices are superior to mine.
If your mind is made up, I will not pointlessly annoy you by trying to convince you. I will continue trying to convince others.
In 1983, almost everyone thought my ideas were foolish, but I did not let that stop me, so now we have the GNU/Linux operating system.