the arrogant hudson has to go, page-8

Well done.

The international airline seat utilisation statistics have a significant lag: latest is for July 2023, so not directly comparable with November.

Thai AirAsia X had 84.4 per cent of seats occupied inbound to Australia then, but only 46.4 per cent for its flights departing Oz.

So passenger numbers vary a lot by direction. July also has school holidays.

Mid November is too early for the parents and kids (and many others) travelling to Thailand and numerous other destinations for Christmas holidays, and also (similar to Philippines) IIRC the weather won't be quite as pleasant as in say January or February, so one wouldn't expect flights to be full to the gills.

November (like February and May) is typically one of the three least well patronised months for airlines operating out of Australia.

Given Thai AirAsia X only operates three days a week from Sydney, perhaps its lack of a daily schedule mitigates against many choosing it. Operating daily (even though occasionally a flight might be cancelled) gives people psychological assurance that they'll be able to get back home relatively promptly if plans need to change, say because of the death of a family member or close friend.