Not sure what there is to discuss about this, but there are regularly comments in the forums that people want a 5G plan, but they are only available through Telstra, Optus and Vodafone directly, not through the MNVOs that use the carriers and often often better deals.
Well, now, if anyone hasn't seen them, there are reports in the specialist media that Telstra is planning to open up its 5G network from July. So watch for the bargains.
https://www.itnews.com.au/news/telstra-to-open-its-5g-networ…
SpinTel has been offering 5G plans through Optus for some time now