Provide way for event node author to grant edit access

I don't have a solution as to how to implement this, but would love the maybe have all organizers have edit access to add sponsors, speakers, CoC contacts, etc

this would help a lot.
I would like to go easy with that, and the funn node could be editable.
So it could be a "simple" rule, where all Organizers of the event hav also Edit rights of that node/event!

We’ve done an initial port of node & field access customizations to the modern version of the site. So we don’t do this work twice, it should wait for events to be migrated to the modern site.