I think the main problem with old laptops being discarded is one of software & OS release cadence more than hardware relatability.

My accountant has used the same 4 apps since the turn of the century. Yet the industry has created a situation where they’ve needed to buy 10 new computers to keep up, even though they still just use email, spreadsheets, web, and a word processor. They’d happily be in XP if it were still on offer.

The only meaningful productivity boost from the hardware side of things for the overwhelming majority of knowledge workers over the period was the introduction of SSDs and wireless network cards.