Places like Italy and Spain have already gone through a long lockdown which was several orders of magnitude more strict and serious than anything in Australia, and also got the cases pretty much down to nothing. Having done that once, there is pretty much zero appetite or economic possibility to do the same again. It seems to be accepted now that a certain level of the virus has to be tolerated, and that includes allowing stuff like cycling races to go ahead with just minor restrictions. I don't think its being casual, more an awareness of the problems that shutting everything down caused, without really resolving much in the long term.
So hopefully they will keep the cycling going; but I do fear that things like the Giro and Vuelta are kind of easy and visible targets if governments want to look like they are taking stronger action. Also, it is a bit devaluing to a great race like the Giro, to have such a low quality GC battle, but it surely won't produce a worse winner than 2012 anyway.