The first technology wasn't the steam engine, it was eating beef instead of just grain, and having cattle pull plows. We don't think of that as a huge technological revolution, but it was a dramatic efficiency gain at the time. It wasn't a new invention, but there wasn't enough surplus to deploy it widely before that.
One of the many, many descriptions of this is here (many because this is the mainstream theory): https://cepr.org/voxeu/columns/black-death-and-industrialisa...
The first technology wasn't the steam engine, it was eating beef instead of just grain, and having cattle pull plows. We don't think of that as a huge technological revolution, but it was a dramatic efficiency gain at the time. It wasn't a new invention, but there wasn't enough surplus to deploy it widely before that.