As we know, buying an older phone can be a big security risk, as it might not get updates anymore. How about laptops? i would install Linux on the laptop. Is it a security risk to buy a used and refurbished computer from maybe 2019?
primary difference between a computer and a phone in this regard is that old comouters can perfectly well run modern Linux. with a phone, you're lucky to have root at all so good luck updating it yourself.