Hypothetically, When you buy an iPhone, do you expect to also get the latest model when it is released?

That being said, Apple also releases iOS updates to previous phones, even after they've been paid for.

If this doesn't seem strange to you, then perhaps the same thought process of buying a specific version of software with the expectation that it will work for several years is not unreasonable.

I see no need for a subscription model on every type of software. I pay you once, you ensure that it's written in a way that will continue to work for years to come. End of transaction, as far as I'm concerned.

Why would you assume that buying software gives you the right to free upgrades as new OS versions are released?

Traditionally when you 'buy' it gives you access to upgrades and support for a period of time.

For me, that is much preferable, especially compared to a model like creative cloud, which only allows cancellations of the subscription once per year, with no refunds.