Usually no.. but I have had an issue with Report Builder reports... they don't show in the assets, but IF the user has any scheduled Report Builder reports (these show up in the legacy scheduled reports (as opposed to scheduled projects) area; those will break - likely cause the credentials to pull the data no longer exist.
I found that one out the hard way 😛
I still like to review all the assets in an account, transfer what is good, delete what is not... remove the user's access from Admin Console, then remove the user from Analytics.
Remember, the user technically still exists in the Analytics when their access / account is removed from the admin panel.... in Analytics they look like the old legacy account and say "not migrated".... (if you have been around long enough, you know that before the cloud login users were added directly to Analytics, and all those users needed to be migrated to the cloud)