Having recently upped my visibility of traffic incoming from the internet, I have to agree with the sentiment that Cloudflare are providing a useful, worthwhile

Having recently upped my visibility of traffic incoming from the internet, I have to agree with the sentiment that Cloudflare are providing a useful, worthwhile service, and the reason that they've grown to the extent described is that they do a very good job at it, and outran their competitors by a wide margin. The internet is a cesspool of malicious traffic. I was wondering why my Lets Encrypt certs weren't auto-updating, and it's because in my recent upgrade to my primary firewall I hadn't setup an incoming port forward for port 80 (because, ironically, everything is served via 443 these days). But Lets Encrypt requires incoming port 80 for its domain ownership verification - or at least the option I'd setup, which was the easiest at the time. I decided to log (to view) the traffic coming in to port 80, and it was a relentless stream. It'll still be a relentless stream now, but it's all bouncing off the external wall rather than an internal one. Same with port 25, and that's gotta be open if you want to receive email. I was actually looking forward to what Cloudflare will do with email protection from their recent acquisition. If I see many repeated attempts at connecting to port 25, I block the full /24 permanently.