Those of us in the work world are consumed by meetings. It’s a huge part of getting things done, or NOT getting them done. Sure, your classes have “meetings” but this is a whole other beast. Corporate meetings fall into two categories, much like class sizes.
There are big meetings, when a large group shows up to be lectured at by someone at the front of the room.
The speakers have info they think is vital to convey. By stopping all company work for their Town Hall, All Hands, or monthly webcast, they are really serious. It costs a lot of money to have everyone stop working at the same time. Pay attention. Just as a giant introductory class might not be the most interesting part of a given academic subject, it’s foundational for everything that will come later. You still need to listen and make sure you’re getting the material down. You’re in no position to guess what’s relevant and what’s not. It’s also a great chance to get a feel for the larger culture in any new job (or with any new client or vendor). How do the folks on stage dress? What do they look like? I’d take it to heart if I only saw really old white guys on the stage or you’re in marketing but the only people ever on stage are the folks from finance and operations. There’s a subtext there.