Of Australian airlines internationally
Qantas offers 23Kg, though this was 20Kg until recently
Pacific Blue offers 20Kg on Go or Blue Saver fares
Jetstar offers 20Kg on economy fares which include a luggage allowance
so hardly the standard to allow 23Kg
Just checking a few airlines that operate or codeshare into australia, from this morning's 1st arrivals ( and ignoring US flights where allowances are different ) up to 0645
Jet Airways
Lufthansa
Singapore Airlines
Lufthansa
finnair
Air Malta
Cathay Pacific
Air China
Alitalia
Korean Air
JAL
Malaysia Airlines
Etihad for tickets issued prior to June 15 2010
all still have a 20Kg limit.
Air New Zealand allows 20Kg on flights from Australia to London
whilst
AF
BA
VS
Etihad for tickets issued since June 15 2010
Allow 23Kg
and Emirates allows 30Kg
Ignoring the anomoly of EY ,
15 out 19 allow 20Kg
4 out of 19 allow 23Kg
1 out of 19 allows 30Kg
This wasn't cherry picking airlines but just going through the list of arrivals at Sydney Airport this morning and does not suggest to me that 23Kg is the norm and in fact seems to support the asserion that 20Kg is the normal economy allowance. Even of the OW carriers in the list 60% have a 20Kg allowance
Since OneWorld was referred to ... The OW Allowances
NO ALLOWANCE - 1 Airline ( AA)
20 Kg - 5 airlines ( CX, JL, AY, RJ, MA )
23 Kg - 4 airlines ( BA, QF, LA, IB )
MX, being in North America, operates generally a piece based system.
More OW airlines have a 20Kg allowance than a 23Kg allowance
Dave