I don't know a single example of technological progress starting from early metallurgy (bronze, etc.) which led to massive unemployment. Do you really think it's all just good luck?

It's good luck in the sense that it's accidental and not essential to technological progress. It's not good luck in the sense of being based on a random element that could have turned out another way.

I suggest that earlier forms of technological progress shift the available jobs in a way which increases the level of skill needed for the new jobs (in comparison to the old jobs) by much less than later forms of technological progress do.