Australia's legal system is Common Law, inherited from Britain. You won't find any kind of enshrinement of rights in our constitution. It doesn't work that way.
> Can you share more details? Source?
You can find the proposed bill here [0]. It doesn't name Facebook and Google specifically, but says that is up to the Minister to designate "digital platform services" that it applies to. Part of which is:
> In making the determination, the Minister must consider whether there is a significant bargaining power imbalance between Australian news businesses and the group comprised of the corporation and all of its related bodies corporate.
Which just so happens to be one of the key findings of a report in 2018 [1] by the ACCC, which may have kicked off Parliament's slow gravitation towards this terrible idea of a law:
> The ACCC is further considering a recommendation for a specific code of practice for digital platforms’ data collection to better inform consumers and improve their bargaining power.
In that report, only Facebook and Google are named, and in the presentation of this law as a good thing, ministers have only named Facebook and Google.
[0] https://parlinfo.aph.gov.au/parlInfo/search/display/display....
[1] https://www.accc.gov.au/media-release/accc-releases-prelimin...