Why do conferences and other academic events still mostly happen offline? Despite the fact that most of the world is now connected with high-speed fiber and even phones can record 4k video, it seems to me that there is a large focus on offline events. Universities invite guest speakers, hold seminars, organize conferences, etc, and most of the content is not even posted online afterwards. Often the events themselves don't include anything more than the speakers doing their presentations, answering a few simple questions and leaving shortly afterwards - all of which could be done on Skype or a myriad of other platforms.

So why is there still such a strong focus on physical presence?
Conferences are not organised for the talks alone. They are more like the academic equivalent of a pool party or a weekend football league. Although on the face of it the purpose might look like spending time in the pool or playing football, people really go there to meet other people.

As a PhD student it took me a while to realise this. Most people attend conferences to get face to face time with other people in thier field, and often the talks act as adverts for collaboration. You'll notice that there are often conference dinners and mixers designed precisely for meeting others.

Every time I've heard someone talk in earnest about what they liked about a conference, it's always that they managed to catch up with a colleague or similar.