wrote
As a matter of minor interest, there's an interesting logic trap in
play here. I think it is safe to say all holders of the airline
transport rating also hold commercial certificates at least in the US.

As I have pointed out before, ATP is NOT a rating, it is a certificate
on its own. My ATP certificate has no mention of the word "Commercial"
on it anywhere. It is not safe to say that ALL holders of an Airline
Transport Pilot certificate also hold a Commercial Pilot certificate.
The ratings on my ATP certficate include "Airplane Single & Multiengine
Land, B-707 B-720 B-727 L-188" and that's all it states.

Now.... there was a time in the distant past when ATP WAS a rating on a
Commercial Pilot certificate, but that disappeared some 45-50 years ago.

Bob Moore
ATP
PanAm (retired)