I tested. I couldn't download nothing.

First I tried to limit number of connections. Did not work.
Then I changed the "Browser ID",
so that it does NOT tell, that I am "HTTrack Website Copier".
You can select anything else.
You have a roll-down menu to chose from.

Maybe that you are "Internet Explorer 5".
But NOT a name that tells this website,
that you runs a website downloader browser.

That server checks out and blocks website downloaders.
I don't think that is so common.
Quite unusual I think.