There used to be a lot less expectation of post-sale maintenance of consumer software in the era where sales rather than subscriptions were the norm. There was also tolerance for higher up-front prices, and for much of that period sales depended on marketing through and validation by a narrow set of relatively trusted discovery channels, which customer the perceived risk to buyers. Now everything is untrusted, no one wants to pay much upfront but everyone expects ongoing support over they've got the thing. I’m not saying subscription is the only thing that works, but it's pretty easy to see that the calculus facing the average vendor has shifted tremendously over time.