So, this isn't any regular conference. This is a conference filled with mostly Swedish politicians, some in government/office and a lot of different Swedish agency officials. Then there's of course some foreign dignitaries, as well as press and a few select normal persons.
It wasn't translated, but in the Swedish press release - they note that "Myndigheten för Samhällsskydd och beredskap", the Swedish equivalent of FEMA in the US - had at least one official agency staffer connecting to their agency e-mail server over this insecure/open network.
That said, most conference attendees are at the conference in their official capacity, ie. at work.
If that is a security risk, then they ought to make the mail unconnectable outside their own network and demand VPN usage. You cannot blame the person for a poor security setup within his organization.
It wasn't translated, but in the Swedish press release - they note that "Myndigheten för Samhällsskydd och beredskap", the Swedish equivalent of FEMA in the US - had at least one official agency staffer connecting to their agency e-mail server over this insecure/open network.
That said, most conference attendees are at the conference in their official capacity, ie. at work.