I would tend to agree with that statement. IME, the level of English of AF staff that I have been in contact with has always been reasonable and certainly more than appropriate for the job. Sure, it can sometimes be heavily accented and they may sometimes struggle a bit to understand some more difficult accents (don't we all ) and they may not be quite as fluent as some of their counterparts in airlines like KLM or SAS, but that is normal and perfectly acceptable.

I am not sure that I would necessarily say the same with "any other reputable international airline." While I have never encountered difficulties on European or South American airlines, communication in English with some members of cabin crew has on (admittedly relatively infrequent) occasions been rather difficult on some Asian airlines or on Turkish Airlines (although, of course, there have always been on board other members of staff with greater fluency to help).