[snip arguments]
Do not become the internet firewall for your large customer base... it's
bad.
Okay, so please allow me to alter the argument a bit.
Say we agreed on:
1. Security is THEIR (customers') problems, not yours.
2. You are not the Internet's firewall.
That would mean you would still care about:
1. You being able to provide service.
2. Your own network being secure (?)
In a big outbreak, not for the WHOLE Internet, I'd use whatever I can.
It can easily become an issue of my network staying alive.
Blocking that one port then might be a viable solution to get a handle
on things and calm things down.
Naturally though you are right again, it is a case-by-case issue and can
not be discussed in generalities.
Gadi.