I agree, I just pointed out your inaccuracy that it will straight up never work.
The quoting of my sentence you have executed here is quite evil since it suggests the wrong circumstance of discussion and implies another meaning. My full sentence was

But it isn’t hardcoded to start the request on port 80, ignore any HTTP code redirects and fail outright if it can’t find the token.
and the important part of my sentence was the combination of “hardcoded to start the request on port 80” AND “ignore any HTTP redirect” AND “fail outright”, since you said

Many people running Cloudflare set Cloudflare to automatically redirect HTTP to HTTPS, and that makes port 80 on the origin server unavailable, and that prevents HTTP-01 challenges from working.
and this implies that the reason of the HTTP-01 challenge failing is the redirect alone, which is not true.
Also, strictly speaking, a redirect does not make port 80 “unavailable”.