This is true. I had some bad actors from the ComCast Network at one point. And unfortunately also valid human users of some of my "things". So I opted not to block the ComCast ASN at that point.
Yes, I would! I love Caddy's set and forget nature, and with this it wouldn't be different.
Especially if it could be triggered conditionally, for example based on server load or a flood being detected.
I would be interested to hear of any other solutions that guarantee to either identity or block non-Human traffic. In the "small web" and self-hosting, we typically don't really want Crawlers, and other similar software hitting our services, because often the software is either buggy in the first place (Example: Runaway Claude Bot) or you don't want your sites indexed by them in the first place.