I’m with you but, to be 100.1% honest, we don’t know where MB measures the SPL of its cabs.
We may speculate that it is at 1kHz but there are no credited TB members which are also MB’s employees/designers (the same applies to other brands) which can provide further clarifications on what their internal testing and measuring procedures are.
Certainly Mesa proudly states what they correctly do and everybody else, for correctness and completeness, should do the same, but .. maybe MB does this as well .. who knows?
Being open and substantially correct in this regard is certainly a merit for Mesa however.
In any case, super good American stuff, also sold at a good price in the USA, when imported in Europe becomes immediately much more expensive making it almost unbuyable unfortunately; hence, I, as a poor hobbyist, although not so bad at playing (allow me to say so), will likely accept to buy a cab which may be slightly less sensitive than another one (presumably) if I can purchase it at half of the price (in Europe) of the better one.
This for the sake of completeness and supposed internationality if the forum.
Cheers