You do not say how long this has been going on, but migrating 80,000 photos takes a lot of time. They need to be uploaded to the cloud, so this could take days depending on the speed of your internet connection.
I started the migration on Sunday. Pictures started showing up on Monday and seemed to finish syncing with LR Classic Tuesday. I realized there were no changes overnight Tuesday. Nothing happened yesterday at all... LR showed the same status all day.