Paywalled article (It's also nearly a year old). I am very suspicious of the parts I was able to read:
Comparing to the IRS seems almost useless. Anyone who has ever had to deal with the IRS can tell you it's severely, severely under-funded.
Quoting the Canadian Taxpayers Federation like they're a neutral voice doesn't give me a lot of faith in the rest of this article. They're an astrorurfing, libertarian organization.
I don't know anything about Australia's tax system or how well it's run, but it's curious that they have roughly half the staff Canada did before this hiring spree with almost 3/4 the population.
I would be interested to read a comparison of the CRA to other taxation authorities throughout the world, to see what we could learn, but I didn't find anything of that nature before the paywall.