Earlier quoted context omitted.
> the only other real possibility is to legislate that such updates be made available for N years as part of the purchase conditions I am unclear why this is not the preferential solution here. "Don't sell lemons" is a societal good.
It drives prices up in equivalence with subscription pricing over the typical lifespan. (i.e. not obviously better or worse)
Frankly I think the better option might actually be the reverse: a mandatory payout to every customer for every nontrivial security defect. Not sure how you'd adjudicate it, so it's pie-in-the-sky, but take it out of the realm of the class-action lawsuit and see how serious these manufacturers become about correctness.
Businesses fear only the big stick; it should be swung on the consumer's behalf.