> I repurposed an old gaming PC with a Ryzen 1600x, 24GB of RAM, and an old GTX 1060 for my NAS since I had most of the parts already
> I wish people would understand that waste is waste
I think the point is that the configuration from the post can easily run as low as maybe 30-40W on idle, but as high as a couple hundred depending on utilization. An off-the-shelf NAS probably spikes at most in the ~35W range, with idle/spindle-off utilization in the 10W range (I'm using my 4-bay Synology DS920+ as a reference). Normally the biggest contributor to NAS energy usage is the number of HDDs, so the more you add, the more it consumes, but in this configuration the CPU, the RAM, and the GPU are all "oversized" for the NAS purpose.
While reusing parts for longer helps a lot for carbon footprint of the material itself, running that machine 24/7/365 is definitely more CO2-heavy w.r.t. electricity usage than an off-the-shelf NAS. And additional entropy in the environment in the form of heat is still additional entropy, whether it comes from coal or solar panels.