It may or may not be relevant to your case, but every time a story like this comes up I will remind people in general that fiber-optic cable is 50 cents per meter (probably $1 per meter Australian), wireless links cost equipment and a regulatory approval fee and are easier in less densely populated areas, and there are tons and tons of stories of people dissatisfied with their ISP creating a better competitor, your neighbours are likely as frustrated as you if they use the Internet, and there is no minimum size to an ISP.

I'm not sure there are tons of stories about people creating their own ISPs in Australia are there?

I know of companies that set up competing wireless infrastructure, and even one suburb around here that is served by a private network rather than the national network, so I guess they did it, but they have (at minimum) hundreds of customers.

At that price I might be looking at $1k-$2k just in fibre-optic cable, before we talk about any of the necessary equipment or the price of actually installing that cable underground. That covers starlink for quite a while.

If you set up a wireless ISP, you become a carrier and that is expensive.

TIO membership, the carrier licence fee, telecommunications interception and data retention obligations create recurring costs in the thousands of dollars a year before you serve a single customer.