> Sites need to deal with Australia
Do they? The UK’s population is more than double of Australia’s and some websites (e.g. imgur) are outright blocking the UK.
imgur blocking the UK is not due to ID verification, but because they refused to stop making money off childrens data.
All publicly-listed ad delivery systems like Meta do in fact need to deal with high-income countries.
They can't afford to and will never strike off 100m Brits and Aussies, and that number will only rise with more high-income countries making regulation.