I guess the answer is that Fairfax are, to a degree, quoting from the source of the data. Most things in aviation, even the commercial side of it like seat pitch and the size of the IFE monitor, are still given in imperial units. It arrives to the Fairfax journalists like that and journalists have to make the conversion themselves (hopefully not quoting to too many significant digits).
I don't know if this is followed all the time at Fairfax or other publications, but sometimes the distinction can be important. For example, you don't want a case where a company providing information to Fairfax goes, "We didn't say that the pitch was 96.5 centimetres - we said 38 inches!"
I still get plenty of pilots - even Qantas or Virgin Australia - that report their flight altitudes in feet. It might be tradition, but there are also other factors; for example, Flight Level (FL), important in aerial navigation, is based on imperial units (hundreds of feet). Speed is still in knots, even though it is conveniently converted for us in the passenger cabin if you look at the inflight map show. Interestingly, frequent flyer currencies are often based on statute miles, even in metric countries. Very few programmes - LAN LANPASS comes to mind - are based on metric units.
That said, not everything in aviation is imperial. Fuel load is in tonnes (not tons), or litres. Same with loads, viz. passengers, luggage, cargo, etc.. The magic number 23kg, which is a common maximum weight for an Economy class baggage allowance, was actually derived from its imperial equivalent, the more "rounded" 50 lbm.
I don't know exactly where the "industry standard" for things like seat pitch, width or the sizes of screens got set for imperial, though I guess it's been like this for a long time, and one of the major (if perhaps the biggest and oldest) players in the aircraft game is based in the US. Competitively or commercially, it probably didn't make sense for, say, Airbus, to try and market their craft in metric and forcing their potential customers to try and decide between two totally different looking sets of numbers (although that said, most of those numbers likely involve a mixture of imperial and metric measurements!).
I'm reading a lot of recipes at the moment. Converting degrees F to C is not a big deal, but imperial cups to metric cups and fluid ounces to millilitres is a pain in the backside.
Any good engineer will need to be ready to deal with both sets of units, and convert fluently between them (as long as they get / look up the correct conversion factors).