Isn't that the other way around? If I buy a license and I find a bug a year later, there's no guarantee of a fix. If I am subscribing, I can threaten to cancel.
It was a direct response to the parent.
Also, if you loose access when you stop subscribing that is actually much harder to do compared to not paying for an upgrade if you "own" a license of the software.
But rather that companies that don't offer subscriptions can't game on features and bug-fixes just to fish for upgrade fees before people feel (rightly so) ripped off. There is an implicit agreement on the support provided and if the company fails to deliver that people won't play along.