Turning the iPad into a MacBook is far more than some artificial lock.
It requires consciously designing everything to work as both a fully fledged computer and content consumption device. That touches everything from product design, internal hardware, thermals, operating systems, frameworks etc.
It has a processor, ram, storage, video output, Bluetooth and network connectivity. I'd say it's already fully functioning computer designed to do any computing task. Of course, manufacturer wants it to be a locked down appliance, but its predatory behaviour is not a reason to sheepishly accept the status quo.
And what you say about 'consciously designed ...' amounts to nothing meaningful. Have you seen what hardware people have been running Doom on?
iPad's hardware is already a perfectly usable general purpose computer. It is very portable, unlike your fridge, and has powerful processor and high-capacity battery, unlike your watch. The only problem preventing its use as a general purpose computer in a sense of Macbook is a lock by the manufacturer, which prevents loading a proper OS on it, and the absence of hardware specs, nothing more.
Reductio ad absurdum just to drown out the merits of the parent post. Your iPad is far more capable than those three devices. It should be able to do what the user would like to do.
And an iPad is nowhere close to the safety-critical nature of the other computers. There is no defence for its locked down nature.
It requires consciously designing everything to work as both a fully fledged computer and content consumption device. That touches everything from product design, internal hardware, thermals, operating systems, frameworks etc.