While it is stupid, I can understand while it still happens. Even though there are no smoking signs everywhere, the fact all our aircraft have ashtrays (as required by law to safely dispose of one in case someone does light up) can send a very confusing message in particular for first time travellers and non english speakers.
Generally anyone caught smoking won't be arrested, but a firm warning. 2nd offence you should probably expect a visit from the authorities on arrival.
Whilst I can see where you're coming from with this argument, perhaps it may expose my lack of empathy, but I still believe that no one has any excuse whatsoever to light up on board, and nothing should change on the corporate side because there is no significant confusion that may send "mixed signals".
I can see your argument as to why someone may do it, but overall it is still 100% (alright, 99%) their stupidity. (Just like someone may rob a food store because they are hungry - the latter being the reason - doesn't mean it was right; shoplifting is a crime and the act having carried out relied solely on the stupidity of the offender).
Any traveller these days must be prepared to face the reality that the lingua franca on
any airline (some select ones excluded for rather obscure reasons) will be English (and / or the airline's country's language). They have had to pass several hurdles as it is to actually get on board - some may be in English, some may be in the language of the airline. Yes, you can nod and not know a lot to get on board these days, but in saying that that is not a legal excuse. (Same thing behind signing a contract and not reading the terms, then feigning ignorance).
If I recall correctly, the QF safety briefing for flights to (and possibly from) HKG are announced in English and Cantonese, and subtitled in English and Cantonese Chinese. Unless the video was broken and a manual safety demo was done (in which case, the CSM would most probably only do it in English), I'm sure the video still has a message near the end that smoking is prohibited, and I'm sure this, too, is translated.
The no smoking sign (a cigarette with a cross-line (or even a 'X') through it) is so ubiquitous, I would highly doubt that anyone would be able to claim that they do not know what this means, much less a smoker. As if a first time traveller has not seen this sign before in a restaurant, at the airport, in some other public place... why would they see it on a plane and then decide to flout it? (Yes, I realise there are places in the world which have smoking regulations almost the direct inverse of what we are used to in Australia, but surely they still have
some places apart from onboard aircraft where you cannot smoke).
As stated on the video, smoking
is a fire hazard, and if anything more (at least these modern times) it is an amenity issue. That is why, with already a multitude of warnings about, I believe there should be no leniency for any offence, including the first, which should include mandatory detainment.