Vegetation is expanding at high altitudes in the Himalayas

In Eurasia, the consensus is "mostly climate change." For Australia, it is "mostly human." For South America and Africa, I don't know what the consensus is.

For North America, the only strong consensus you will find is for both factors to be implicated, with vehement disagreement over the degree to which factor is stronger. The megafauna extinction event happens to occur at the same time as both the Clovis period and the Younger Dryas onset, which means the timing doesn't really work better for one or the other factor. However, we have since learned more about human migration to the Americas (humans arrived a few millennia before Clovis, although the exact amount is disputed), as well as the nature of the Younger Dryas (sharper than expected [1], with the worst effects occurring in some portions of North America). A more realistic approach would be to view North American megafauna of suffering a variety of negative population pressures, with humans providing more of a coup de grace rather than the primary driving factor of their extinction.

[1] 10 degrees Centigrade in less than a century, maybe even a decade. In other words, sharper than the current climate change concerns.