I agree about the need to clearly register disagreement, but I'd opt for slightly less shock... I'd say, calmly and sternly "that is entirely inappropriate." I'd then call on others in the group to register their disagreement.
For this reason I am fond of Jonathan Zittrain. Not that he particularly aligns with Assange but he is very good at presenting these issues in a compelling manner.
This year he seems to be continuing with the theme: Taming the Chaos: Can we build systems that actually work? [1]
[1] https://fahrplan.events.ccc.de/congress/2018/Fahrplan/events...