Nikon has always said that non-AI lenses cannot/should not be used on later bodies. The D7000 manual (section Incompatible Lenses - see Index for Compatible Lenses) includes "Non-AI lenses" as Not compatible. The D3?00 and D5?00 manuals say the same thing. I thought the concern is about damage to the electrical contacts in the body, which were not in older bodies. Seems dumb to risk an expensive DSLR to try to use an 50 year old lens (that can be converted to be compatible).
Back in the day (1970s, 1980s) Nikon would convert non-AI lenses to AI for a very small charge, like $20 or $30. They don't anymore, but there are third party that still do, for higher price.