There is conservative and then there is behaviour limiting on anxiety. As stated above, headwinds/tailwinds are factored in the RTOW tables or performance software.
I would say ask the guy if he can explain the reasoning above, as you want to learn some command traits, but high chance you’ll get another unreasonable answer.
There is always the solution of going TOGA - but certain of these operators are known to ring up Captains and berate them for using TOGA.
Is this for real? I’d expect a ring if one day you have to offload half of the aircraft in 40kt headwind, because you were “conservative” and took 15kt tailwind and 30C higher OAT, but not for the use of TOGA.
With the old Airbus performance manuals it was always an option for a Captain to reduce the Flex temperature if he so desired (yes, there are many good reasons why he might want to do so, and the book outlined the method).
Interesting. The Boeing’s T/O thrust system is in my honest opinion much better and more flexible than the Airbus one, as you normally have 2-3 derates available and each of them can be combined with an assumed temperature vs just FLEX or TOGA on the Airbus (A320 at least), thus giving one many combinations to choose from, as appropriate on the day.