I'm still using a 2009 HP 6910p (Core 2 Duo T7300 CPU) bought used for 120E in 2012 or thereabouts. I use it for C (mostly, but also py, haskell etc) programmin

I'm still using a 2009 HP 6910p (Core 2 Duo T7300 CPU) bought used for 120E in 2012 or thereabouts. I use it for C (mostly, but also py, haskell etc) programming, Arch Linux + i3 WM, it has a great keyboard, everything works out of the box. There are very few things a modern laptop would bring me that this one doesn't. At home I have a much more capable development desktop, and at work an even better (i7 4790) computer. But the thing is, apart from the lower power consumption (from 20W-30W regular usage down to 10-20W, depending on the configuration), there's no point in upgrading for me. I'm still a student, so I'm still playing occasionally with things like OpenGl shaders, game programming, machine learning, and other orthogonal areas of computer science, for that I use my desktop. I don't think a laptop is that great for working (sub-optimal posture). But sure, there are people who need bigger screens/ more horsepower (high-performance computing/ those coding in memory hogging environments). But for Linux, and low-level programming, a slightly older machine definitely suffices. Granted, I live in a part of the world where one can live reasonably for a few months-up to a whole year for the price of a rMbp, and I value financial independence, freedom, more than the status signaling ability a Mbp could bring, but I do see why others might value it more.