You're right that it is an unfair comparison to the state-of-the-art. And a lot of people are considering upgrading their older systems not because those systems are slow or under-performing but because of other factors like portability, dying batteries, and failing hardware. I think their point is that an iPad can be a suitable replacement for a lot of people not necessarily looking for an upgrade.

My mom has a behemoth of a Dell laptop from 7 or 8 years ago. It's an i7 with 8GB of RAM and if I dropped an SSD in it for her then it would hum along just fine. It has performance parity with my maxed out Yoga 2 from a couple years back. She's looking to upgrade it not due to performance but because it's heavy, the battery is dead and a replacement is $200, and she want's a 10-key.

My point is that performance is no longer the driving force compelling people to upgrade.