Weird, the page loaded once and then on a revisit (going back to read comments) Firefox gave a "Secure Connection Failed" error.

Curl fails too:

    > GET /about-us/view-all-content/news/five-eyes-cyber-security-agencies-statement HTTP/2
    > Host: www.cyber.gov.au
    > User-Agent: curl/8.5.0
    > Accept: */*
    > 
    * TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
    * TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
    * old SSL session ID is stale, removing
    * HTTP/2 stream 1 was not closed cleanly: INTERNAL_ERROR (err 2)
    * Connection #0 to host www.cyber.gov.au left intact
    curl: (92) HTTP/2 stream 1 was not closed cleanly: INTERNAL_ERROR (err 2)

Some hours later, exact same problem: First page load is fine, then after a force-refresh the site stops responding even to curl.

So not a coincidental problem with the site being overloaded, perhaps they've misconfigured some kind of "No Non-Austrialn IP's Allowed" system?

Maybe next time I'll try accessing their "Contact Us" page, and gradually find a way to notify their staff. :P