After learning that the European union and the UK will ban most fluorescent tubes by 2023, I am wondering if this same ban will affect fluorescent tubes in Australia.

Maybe with some delay?

It’s seems to be slightly accelerated where I am?, I was in one of our hardware stores yesterday afternoon called Wickes, and took a look at the fluorescent tubes stock.
They still have plenty of Sylvania T8 tubes in 5’ (58 watts), and 6’ (70 watts), but all the 2’ (18 watts), and 4’ (36 watts), have gone!, you can only get 2 and 4 foot in LED tubes now!
Unusually though, another one to be banned, (the 16 watt 2D lamp), there was still a big pile of?
T5 in 8, 13, and the new larger size wattage are still plentiful also, but I think some of them are exempt?

It’s the first time though I’ve ever seen no T8 in 2 and 4 foot for sale in any of our hardware stores here!

I think these bans effectively come after the lamps are already extinct by "natural forces"(the makers stopped producing them because the already too low customer demand)...
Generally the bans left the specialty lamps sold with only low volumes for long time alone and concentrated just on the (once) main "industry workhorses", which were in use everywhere.

 There already few states in the US that bans fluorescent lamps.    I think the quality of fluorescents will go down hill.
  I find there one independant fluorescent maker then u got servant.  My advice is to stock up on favorite lamps while u
 Can.  Lamp maker dont care about general public.

I don't aware about a fluorescent lamp ban.

Lamp maker dont care about general public.

Well, they do, always did and are in fact supposed to care about profit making the lamps they make.
The thing is, things like lamps need to be produced in quantities in order to reach a reasonable unity cost. And of course they have to be sold in such quantities, at a selling price allowing decent margin. Lower the production volume, the higher the unity production cost, so the higher the selling price has to be.
Problem with the fluorescents today is the same as with medium pressure mercury lamps the last half century: There aren't enough customers willing to pay that price to buy that volume of lamps, so producing them does not make profit anymore. And to make profit is the main and only reason for the existence of those companies, so it should be a matter of course they will make only products making profit.
Yes, mainly with production of incandescents, most companies were just waiting with zero margin for others to quit the business sooner, so they will be able to boost selling prices, but that did just led to a very long standoff war, terminated only by the incandescent ban cartel (ensuring all will quit the business at once, so no one able to pump up prices will remain). After that lesson from the incandescents, with fluorescent businessthey don't repeat that mistake (enter similar standoff) and just quit the business once the profitability of a certain lamp type become low or nonexistent. Mainly because the main fluorescent customers were businesses, without that much of sentiment of sticking on the technology like home consumers were with incandescents. So once LEDs became viable and cheaper to own alternative and the customers went over lighting system overhauls, the fluorescent market is just gone.

In Australia, nothing fluorescent has been banned and you can still buy new tubes and fixtures at hardware stores.

T12 tubes are no longer sold in stores but you can still import them via online shopping websites. This is because T12 tubes are not actually banned in Australia. Demand for T12 tubes began to drop after ELMA shut down in 2002 and by the time the Australian Government started to introduce new environmental and energy saving regulations, the remaining stocks of T12 tubes had dried up and banning T12 tubes was no longer a viable option.

Currently the only lamps that have been banned in Australia are incandescents and I don't believe there is any plans to introduce a ban on fluorescent tubes.

All fluorescent lamps are going to be discontinued in Switzerland by end of August 2023. See here for further details: https://slg.ch/ausphasungsplan/  (in German)

Australia banned the sale of halophosphor tubes in all sizes except those for special applications like the miniature T5's in around 2010, about the same time as the incandescent lamps were banned.

As far as I'm aware there is no talk of banning linear triphosphor tubes from sale here yet. Almost all fluorescent tubes are coming from China, therefore manufacturing supply won't be drying up anytime soon for the tens of millions of fluorescent fittings still in use here.

Generally the reasons people are swapping them out for garbage LED replacements is due to the lower running costs as power is getting very expensive, and not because of trouble getting the tubes or an impending tube ban, as I said I haven't heard of this happening yet. However this saving is  cancelled out by the cost of replacing the LED fitting in 1-2 years time when it fails and can't be repaired.

The problem is that power and maintenance costs come from different budgets and they don't talk to one another. 

Even with the 1..2 year lifetime of the cheepeese LED's, they are (in the home use formats, so less than 2000 lm per installation spot) way cheaper in the total than almost any other light source right now. They don't last that long, but cost about 3x more than an incandescents (or even less than that if speaking about really low power ones, so still quite a savings on the running cost), yet still they do offer reasonable efficacy. Maybe not as high and mainly not as good light quality as the good quality ones, but still 8..10x lower power than incandescents is a lot of money for the electricity. Thing is, today even the cheapest LED's are beyond 120lm/W. What they are lacking behind the good quality ones is the reliability (lifetime inthe 1k hour, rather than the 10+k hour the quality ones) and light quality (with CRI70 you need 30% less radiated power than for CRI90 with the same lumens, so reducing the CRI is the common way to boost the lumen figure for the given power level with an older, cheepeese LED technology)

Fluorescents of such power levels (1000lm range) are either moderstely priced but way less efficient (60lm/W for a 18W CFL spiral of similar cost as the same output 120lm/W 8W filament LED), or the heck expensive (a F14T5HE system for at least 5x higher prices than the CFL's, yet you are still barely at 100lm/W). So you can never make the cost sum (purchase plus electricity consumption) anywhere close to those cheepeese LED's. Plus the fluorescents won't respond well on frequent switching, so for the same task they will run way more hours, so consume more energy.