Almost makes it sound like if Horses alone were introduced, but no other white man colonization, that the Indians might have wiped out the buffalo also, if left

Almost makes it sound like if Horses alone were introduced, but no other white man colonization, that the Indians might have wiped out the buffalo also, if left to their own devices. Wouldn't this be more in line with other megafauna extinctions? The only reason Indians didn't also wipe out this megafauna was a technology change, the addition of horses.