Re: "five year old servers and four year old PCs"
Come on, a PC in a business environment can work 6 years just fine. Managers will just have to put up with not getting the latest and greatest to surf porn with on the job.
At my current place of work, once upon a time I had a hole in my equipment replacement cycle. This was filled by picking up a bunch of refurb HP DC7700's to replace some old WinXP boxes to meet the deadline for getting shot of those. These PC's came with a refurb license to Win7 and some years later I spotted an opportunity to buy some things that we did want by keeping some of these boxes in use for an extra few years so a good half of these boxes ended up with a life extension by replacing the HDD's with SSD's, stuffing them full of ram (gained from robbing their peers that were being disposed of) and gaining a Quadro multi monitor card to give them a pair of screens.
They'd all been removed by 2020 as Win7's EOL meant they'd finally been replaced with actually new PC's. They were in a neat stack waiting to be disposed of properly (WEE disposal) when the pandemic hit and we didn't have enough laptops for issue for home use, so we installed Win10 and issued the 7700's; some of which still haven't come back. (and to be fair, we did say that we didn't particularly want them back and people could keep them if they wanted them as a free gift...)
They are now 16 years old and running just fine for acting as a thin client for remote access, and reportedly are fine for doing kids homework, web browsing etc.
I'm unconvinced that at replacing desktops every 3 (or gasp; 4) years is really required.
For that matter I've got a HP Proliant 380p G8 running 2012R2 that is over 10 years old; and it's still absolutely fine. (although as a replication spare for DR it's not exactly got a high load...) For that matter, I've actually floated the idea of buying an additional server 2022 license for it to use as a DR testbed when 2012R2 comes out of support in October and that's probably going to happen because the cost is trivial for the capability delivered.
Why throw things away that still work perfectly? Obviously you don't stick the old hardware in mission critical roles, but they are perfectly capable when managed correctly; typically receptionists etc don't actually need a 32 core CPU with 128GB of RAM...