Ref. https://uk.reuters.com/article/uk-uber-britain-tax/uber-face...
Unless you're a taxi driver, when you need to register regardless. They carved that out.
The ato claims this is because[1]: 1) to avoid the confusion that would be created if some taxis had to charge GST and others did not 2) avoiding the added problem that would arise if a passenger was using a taxi for a business trip (creditable acquisition). In this instance, the passenger would want to be able to claim an input tax credit for the GST included in the fare 3) meter rates are set by each state authority and after 1 July 2000 all meters were adjusted to reflect the GST. If some drivers were registered and others were not, all would be collecting the higher rate. This would disadvantage drivers who had to be registered if the ordinary registration turnover threshold applied.
Interesting point of view in that specific case.
[1] https://www.ato.gov.au/Business/GST/In-detail/GST-issues-reg...
https://www.icaew.com/insights/viewpoints-on-the-news/archiv...
This is the problem with having conversations about tax law: the vast majority of people have no idea what they're talking about. Worse: the vast majority of people think they know what they're talking about.