Mine died last year and I upgraded to the 16" m1max. I was not happy to spend the money, but I think I can easily get another decade out of this new beast
My main concern buying old PC laptops is screen quality. It still possible to buy a laptop with a shitty screen in 2022, even a brand new one.
Company issued laptops are also weird. If you replace laptops every two years, the why buy the top of the line model? Sure some jobs just benefit from the exstra resources, but even many developers could easily do with less.
If getting new hardware makes an employee happy and/or allows them to get a job done even slightly faster, it's basically free to the company, so why not?
A personal machine is a very different cost/benefit calculation to a work box.