Security vulnerabilities generally aren’t considers latent defects under warranty laws (at least not in NA). I’m not sure what the tech world would look like if it were - for one thing, software teams would probably need a P.Eng. on their teams to ship. For another, using open source software would be even harder to do without an intermediary like Red Hat who would be willing to accept tort liability.

At any rate, your software vendor has no legal responsibility to provide you with security updates. Maybe they should. But you’ll pay for that anyways. How do you want to amortize those security updates? By paying the dividend discount price of the updates up front and risk having the product abandoned in a few years (cheating you out of your ‘dividend’), or by paying directly through a subscription?

If you are paying for a subscription there isn’t necessarily an incentive to provide security updates even more, since they have the functionality of your app hostage if you decide to cancel and the automatic monthly billing has no ties to the quantity or wuality of updates they push out.

That makes no sense - you have it completely backwards. Their incentive to provide me with timely security updates is my continued subscription fees. On the other hand, if you pay the dividend discount price for those security updates up front, they have every incentive to stop releasing updates and cheat you out of your update ‘dividend’.