There is no delay for other countries, at least for Employment based green cards. There is some fixed number of employment based green cards that are awarded p

There is no delay for other countries, at least for Employment based green cards. There is some fixed number of employment based green cards that are awarded per category(EB1,2,3) with rollover between categories. The reason why there is a delay is that there is a country-wide cap on a percentage of total green cards awarded that year. So countries with higher number of people immigrating have a queue. If there were thousands of Australians immigrating, there can be a queue there too. I am not sure about Canada though, as there maybe some other category for it.