Hi Sam
No, I don't think I was kidding you. What I meant is a bit complex, but let me try to explain.
One does not need special shoes or footbeds or medical assistance for any foot shape within the ordinary human range – which can be very broad. Our ancestors managed very well thank you for hundreds of thousands of years without even any shoes. Arch supports, pronation control, orthotics – they are creations of the spin doctors in the last ten or twenty years.
The word 'orthotic' does imply some sort of significant medical intervention. The dictionary definition is thus:
'(Medicine) the provision and use of artificial or mechanical aids, such as braces, to prevent or assist movement of weak or injured joints or muscles.
[From New Latin orthsis, ortht-, artificial support, brace, from Greek, a straightening, from orthoun, to straighten, from orthos, straight.]'
So when the word is used properly it means that some rather serious injury to the foot is being remediated – like maybe it got crushed under a ton of bricks or similar. But every one of those injuries is going to be unique to the person involved.
Trying to change however your feet behave to conform to some sort of idealistic perfect average both misunderstands the nature of normal human variation and risks serious injury to your feet. In fact, the idea of a 'perfect average' is really just a triumph of marketing spin and snake oil. It's gibberish. Sadly, Nike are responsible for three of the worst spins in this direction. Popular 'orthotics' are a fourth.
Follow all that through and you can see why I said that 'mass-market' and 'orthotics' do not belong in the same sentence – except as opposites. Yes, I know some companies claim to sell 'mass-market orthotics', but they also sell glass pyramids, magnetic healing bracelets based on quantum mechanics, and the Brooklyn Bridge.
Cheers