After the Romans invaded and put the Jews in power, then the Jewish population did greatly increase.
But there were so many previous tribes in Palestine, that clearly the Jews could never have been a majority.
They were so easily beaten by everyone, like the Assyrians, Babylonians, and the Romans, that they could never have been more than a forth of the population or so.
In particular, the Romans discussed who to use as their ruling puppets, and the Jews were picked BECAUSE they were such a small minority.
All colonial imperialists do that, pick a minority as their elite representatives.
That usually prevents rebellion.