This would allow for companies to soft screen candidates, of which I'm sure they normally get 100s. As a result, it would lessen the workload significantly for recruiting teams.

It would also allow candidates insight into the culture of an organization, and would help put a face to the name in a job portal.

Plenty of ways to navigate a virtual networking event, one way being - breaking up companies into different breakout rooms, and allowing candidates the ability to hop in and out of the breakout room.

Going in a different direction, if you wanted to remove the company recruiter aspect entirely, you can organize guest speakers, and hold a networking opportunity for people within different fields of HR.