David Anthony’s The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World is a bit dated, but it’s still a useful read. Papers such as Population genomics of Bronze Age Eurasia and Massive migration from the steppe was a source for Indo-European languages in Europe come out of the tradition that Anthony comes out of. Arguably these thinkers even underestimated the demographic impact of the people from the steppe.
If you are interested in this topic, I think you might find First Horse Warriors: The advent of horse riding changed the course of human history and the genetic makeup of humankind, worth a watch. I think the second half, in particular, will be interesting. Researchers whose names you see only in papers are interviewed. So if you want to put a face to the name, this is your chance.
I would say though that again watching this episode reinforces my point that visual medium is very low density in the information. They had to focus on a few major results and scaffold their visuals around that.
The main issue in the documentary is that researchers still debate the nature of the usage of the horse on the steppe. Anthony and Dorcas Brown have been arguing for an early date of widespread horse domestication, at least as early as 3500 BC. But others suggested a date closer to 2000 BC, around when the light war chariot was invented.