Let's say I have a Magento 2 system that was migrated from Magento 1.
The folks who migrated this system ported over everything in the
core_config_data table. This includes configuration paths that don't exist in Magento 2, as well as configuration paths from extensions that are no longer installed on the system.
Are there tools for automating cleanup of this old data? If not, are there known techniques or workflows for cleaning up this old data?
Are there known bad effects for leaving these unused data fields in the
core_config_data table? (other than future confusion for folks looking at this data)