It's been a while since I tried, but my experience trying to manually set up GPUs was atrocious, and with investigation generally ending at the closed-source NVidia drivers it's easy to feel disempowered pretty quickly. I think my biggest learning from trying to do DL on a manually set up computer was simply that GPU setup was awful and I never wanted to deal with it. It's not that I don't want to understand it, but with NVidia software you're essentially not allowed to understand it. If open source drivers or open GPU hardware were released, I would gladly learn how that works.