Chinaman1119 I couldn't agree more.
I think you summed it up very eloquently. It isn't about minimum requirements but more about common sense. Diversions are costly and if they can be avoided then they should be. No-one wants to be offloaded in some remote airport with poor medical facilities if a proper medical kit would permit the aircraft to continue to a more appropriate place.
If you want doctors on board to volunteer their services then the least they can expect is the basic equipment to do their job.
The authorities may permit less to be carried, but does it make sense in the long run to skimp on these things?
You pays your money and you makes your choice, that applies both to the airlines and the passengers.