Yes... that is ONE viewpoint. I find logic, as well as historical documents, to be a better fit:
"From the Biblical Archaeology Review: 80,000 “Estimating the Population of Ancient Jerusalem”, Magen Broshi, BAR 4:02, Jun 1978
Roman historian Tacitus estimated the population of Jerusalem at the time of the Jewish wars to be 600,000 .
Jewish historian Josephus, who would know because he had lived there during the 60s AD, estimated the number of Pharisees alone to be 6,000 (Josephus, Antiquities of the Jews, 17.42)
Josephus estimated that 1.1 million were killed in the Jewish War, that 115,880 dead were carried out one of the gates during the month of Nisan in AD 70, and that 97,000 were taken as slaves. Josephus (The Wars Of The Jews Book VI Ch 9 Sec 3)"
Joshua was real.
I think it's kind of funny that your own link states that Josephus and Tacitus almost certainly exaggerated their numbers.
You didn't quote that part, did you?