I’m sure you can buy the portable ones we have. Main brands are worldwide, not Australian specific, so people just need to swap from whatever dinky things you are complaining about to the ones we use and problem solved?
Yes, we have restrictions during total fire bans. This doesn’t extend to residences though (and if it does, it’s not policed or there would be widespread riots) and tbh many people still use the portables out and about during bans as gas fed barbies seem a bit innocuous. To be fair, the fixed gas ones at many picnic grounds (gross, and you won’t find many Aussies who willingly use them) never seem to be turned off by councils during fire bans either, and they do have the ability to do this, so they can’t be that worried about it.
ETA They use ones with coals in a regular foil tray that is generally placed directly on the ground, grass or beach. They are then chucked away or left behind. I believe this sort is banned throughout Australia
Don’t know if they are banned here as have never seen anything like what you describe so maybe they are. Then again, why would anyone want such a thing as sounds odd? I’m guessing the only ‘upside’ would be if you went places on public transport as everyone here sticks the portable barbie in the car to take it to the destination as while portable it’s not really suited to public transport. Most people have big BBQ set ups at home (often built and gas plumbed in), the portables are strictly for out and about unless you live in a flat with miniscule balcony. Seem quite a few portable Gozny and Oonie pizza ovens out and about over the past year or so also, so seems they are up and coming.