My father was a paleontologist, albeit 30 years ago. I think what is happening with human fossils is that we have/are reaching a critical mass of knowledge that allows us to pinpoint with greater accuracy where to look. The thing starts to become self-perpetuating.
For fossils in general, there are more of us physically wandering on the surface of the planet, and we collectively are more familiar with what is a fossil, which leads to more discoveries.
As well, due to machinery such as excavators and tunnel diggers, we are digging in places we haven't dug before, either deeper or in hard-to-access rocks.
The big unexplored areas is (1) beneath the deserts, especially the Sahara, and (2) under the shallow seas.
For fossils in general, there are more of us physically wandering on the surface of the planet, and we collectively are more familiar with what is a fossil, which leads to more discoveries.
As well, due to machinery such as excavators and tunnel diggers, we are digging in places we haven't dug before, either deeper or in hard-to-access rocks.
The big unexplored areas is (1) beneath the deserts, especially the Sahara, and (2) under the shallow seas.