They fought the good fight against Apple for awhile - not least of which that they didn't want to pay Apple a percentage of each transaction. But, they eventually all caved to Apple Pay as it was the only way to get it on iPhones which have a majority (56%) marketshare here and people were citing it as a reason why they were changing to the (usually smaller) banks that did offer it.
I am kind of glad they did as I really like the Apple Pay experience and trust the to get it right more than the bank's very hit-and-miss mobile app teams...
https://www.macrumors.com/2020/04/28/westpac-australian-bank...
https://www.statista.com/statistics/861532/australia-mobile-...