Was humanity dying out by the start of this movie?

we will be fine..Trump will fix it in 2024.

The premises for this film are difficult to reason out because they are contradictory. We are told humanity faces fatally declining population, yet the real crisis seems to be depletion of resources, namely food, that are stressing human populations. Large, seemingly nomadic populations of the unemployed and disenfranchised engage in acts of social protest over the proliferation of robotic labour, yet seem well-fed, clothed, and able to support an entertainment industry that coddles their persecution complex by destroying obsolete robots before their eyes that nobody wants anymore, anyways. A mere two thousand years later humanity is extinct, apparently having failed to survive a global glaciation, ostensibly brought on by precipitous, sudden climate change. Whether the acceptance of intelligent robots into human society caused a plunge in human birthrates, or an environmental catastrophe destroyed humanity's eco-niche on Earth, or if present-day humans simply lost the will to live and reproduce, is not stated. We merely have the say-so of a group of apparently intelligent machine-beings who, like ourselves (the audience), assume they are the descendants of early human-engineered AI; Yet, their own records are fragmentary and they therefore cannot verify this, nor do they wish to entertain the possibility that perhaps they themselves are the real descendants of humanity, having evolved during the glaciation and ultimately replaced the earlier model. Is AI a parable about unconditional love as computer programming, or is it a forecast of the next stage of human evolution, beginning with the catalyst of emotional robots? It seems safe, eons later,
to consider Cro-Magnons, Neanderthals, and perhaps even earlier hominids to be our ancestors, but I'm pretty sure none of us really wants them around, nor would they have much of a place in our present society. Clearly these questions have no definitive answers, which is kind of how Kubrick worked.

I have long thought that the actual story of the movie is the demise of humanity and the rise of its eventual successor species, mecha-based intelligent creatures that are descendants of artificially-intelligent, human-engineered, robots. Thus, the movie is saying, even before the apocalyptic events described at the film's beginning, that humanity is doomed. The principal characters of this drama act out a story of an artificially-intelligent android boy, who, to gain the love of the human mother upon whom he is imprinted, forms the desire to become more human ('real'). His descendants, who exist in a future after the extinction of humanity, are still carrying out this program, attempting to gain insight into the 'human spirit' in an effort to learn more about their 'parent' species, and perhaps to incorporate their findings into themselves. The movie ends with the successor species demonstrating compassion, understanding, and kindness towards the android boy, aspects of humanity in which they seem to be interested.