I've seen it a few times on a laptop running Catalina. [MBP 13", quite a few years old]
Funny thing there: command line use of curl:could connect and download it all without any issue at all.
Reboot and everything is fine, and it happens across browsers (Chrome, Safari).
Happened on my laptop while I was working on it in the middle of a session. Might be date or so related as it triggered when the local time was midnight.
One of those I also had trouble gettign the laptop to shutdown (had todo a hard power off on it).