The early Hymenoptera were predatory, like wasps still are.

Bees, which feed on pollen and nectar from plant flowers, instead of catching other insects, have evolved much later from wasp-like Hymenoptera, after angiosperms were already widespread.

So the timeline fits into the story.

> were predatory ... ?

Were they? Sawflies are herbivores, and are at minimum share a common ancestor with those that were not herbivores.

https://www.sciencedirect.com/science/article/pii/S096098221...