Don't play dumb, David. The list of signers is extraordinary and surprising, especially to people like us who actually work in the field. This isn't a bunch of random Twitter people.

More importantly: your comment leaves the impression that there were notable people in the field who had a problem with the letter. If an expert working in messaging security didn't sign it, you and I both know that's probably just because they weren't aware of it (or, at the time, The Guardian's story).