I am currently using an obsolete Windows Vista era laptop with only 2 GB of RAM. It is running Linux, so it's not completely obsolete, but it still has a 32-bit CPU, so I will need an upgrade eventually. GIMP will bog this down if I do anything with high-res graphics. A Raspberry Pi 4 is better technologically, I think.
I also have a Windows 10 laptop that works quite well using GIMP, CAD software, and gaming at moderate to good detail.