I didn't take the earlier point as a hagiographic endorsement of licensed professionals, so much as a comment on the changing mindsets of the people making these hiring decisions, and how over several decades that has moved from a sort of cowboy "anything-goes" approach towards a far more risk-averse one.

Outside of interesting questions like whether amateur tinkerers and hobbyists can be as reliable as professionals are other (also interesting) questions like "what factors drive the way institutions and corporations perceive and react to risk?"