Aren’t the vast majority of people suffering cancer from asbestos exposure the people that worked with asbestos for years?

Sorta kinda. It was much easier to get prolonged asbestos exposure than repeated glyphosate exposure. We used it in everything, including carpets and roofs. The asbestos fibers in those roofs are fine, but the glue holding them together isn't. It's been falling on the ground since forever, but it's accelerating more and more.

Meanwhile, the only people working unsafely with glyphosate are basically a subset of farmers. Now, I've basically NEVER seen a farmer handle chemicals according to the instructions, so within that group unsafe exposure is basically 100%, but it's a much smaller fraction of the population.