Conferences are a great way to exchange ideas and for people in a discussion to feed off of one another's thoughts. Virtual/video conferences can't do that in the same way. There is no electronic protocol that enables multiple people talking at the same time -- if they do, someone gets "stepped on" and his/her idea gets lost.
Conferences are/were not always government and contractor; some were government only.
Yes, conferences should be limited to those that serve a legitimate need; and, not everyone needs to go. But, cutting them out almost entirely has severely restricted the ability to exchange ideas.
In my field, it was previously common for Ambassadors to mingle with Sergeants and Petty Officers; Admirals and Senior Executives to mingle with Majors. Now, we have cut-off the exchange of practical ideas and experience from those at the policy level -- and vice versa.
A horrible loss.
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