What do you mean, "What if"? Non intelligent factors are quite often more powerful than thoughtful consideration with regard to much motivation of behavior. Dopamine production and activity in the brain explains how animals can be motivated quite apart from conscious decision making efforts. By taking taking your analysis , can you predict where the evolutionary process headed, apart from human intelligence?
Evolution is not "headed" anywhere. There is no final goal that evolution is trying to achieve. Evolution is about life surviving long enough to reproduce. If every living thing dies except bacteria, cockroaches, naked mole rats and Keith Richards, evolution is fine with that. Just keeping some sort of life going--that is evolution's "thing".
Although, there does appear to be another "thing" with evolution about diversity of species to fill lots of environmental niches, so after some millennia, if there are environmental changes, more kinds of bacteria, new species of naked mole rats, different cockroaches and other Keith Richardses would appear.
And the world would start anew. It would be kinda scary-looking, but evolution is not about making the world nice and pretty for modern humans, either. If we screw up our habitat, the bacteria and roach-filled world will not miss us at all.