I've gotten 7 years out of my 2018 iPad Pro and, for my use case of video, browsing, and Procreate, it feels like new. And I believe a big part of that is that the A12X was wildly overpowered when I bought it.
I think someone deciding between an M4 and an M5 today should consider its value 5 years down the road, rather than its value today.
Same. Also have a super old iPad Pro, and it still works amazing. I always ponder upgrading, knowing that I’ve gotten so much use and enjoyment out of it, but then get wrapped around the axle about how the CPU is absurdly overpowered for what I do with it (YouTube, podcasts, music, drawing/note taking, reading). It’s my main device at home, too, so I never feel like I need to upgrade my phone - it’s definitely saved me money in that regard, too. :P
I think someone deciding between an M4 and an M5 today should consider its value 5 years down the road, rather than its value today.