For example, I only buy/use old high-end (for their day) business class laptops and put linux on them. They work for everything I need to write and surf.
I also bought an iPhone that was already a few years old and plan to keep it until it stops getting security updates from Apple. I also moved from Android to Apple not because I like iPhones better (I don’t, really), but because the years of security updates (versus maybe one or two, on Android) matters to me.
That’s exactly what I do as well. My laptop is an X280 I got off lease running Debian, and my phone is first gen iPhone SE I’ve been using for over seven years.
I just had a motherboard death recently, and went through the net looking for a replacement that would meet the few requirements I have. Made a spreadsheet of all the one I considered, and in the end I bought the same exact old Dell machine I bought last time. Turns out I made a great decision years ago, and it was still a great decision :)
Even more, now I have a parts computer for when the replacement machine needs something :)