People don't do large-scale public chats with celebrities over email. Think Reddit AMAs, or media interviews and the like. When someone says "This is reporter

People don't do large-scale public chats with celebrities over email. Think Reddit AMAs, or media interviews and the like. When someone says "This is reporter X talking with Alice (picture of Alice + voice + etc. etc.)", it establishes identity that people trust. I guess people could fake this these days, but building up these networks of trust for worthwhile interaction has grown more and more important recently. Twitter's blue checkmark kinda-sorta served this purpose, at least before it died last week. ----- If there was a widespread "Ask me anything" email discussion organized over emails, this identity verification problem would also need to be solved. Since Twitter is an "always ongoing" discussion with various celebrities, the blue checkmark was kinda-sorta the verification you needed.