Forgot you were an expert on ECUs. Given that's exactly what chip tuning is I highly doubt your assumption.
As for 10x the cost. Look at motorbikes now, they (depending on licence) have to be restricted, I highly suspect this would just go the same way.
"must have a restrictor fitted, done on good will, but if you're caught without one expect a hefty punishment."
I asked my mate when he was doing one of my vans (he re-maps for a living), you can;t change settings like that on the fly
the reason they'll cost so much is they'll only be a couple of places authorised to make them, if you HAVE to have one installed, they they ca charge whatever they hell they like, so they will