I agree that it's a sharp edge in the language. Or at least it seems to be -- I've written a little bit of Nim, and never encountered a case where I was actually bitten by 'nil'. The language does have a 'non nil' annotation that can be used when defining structs (and maybe in other parts of the language, I don't recall), so there must have been some thinking about the dangers of nil pointers.

I would still recommend playing with the language for a while. It's quite practical, and the performance is very good. I've used it to write some utilities where I might otherwise use Python, but either needed more speed or needed to use it in a restricted environment where the Python interpreter wasn't available. The experience was mostly positive, and I would use it again.