If people are not updating ASB they will end up with huge amounts of spam. In my case 20k+

Even with post per page set to 200 this will end up in 100 pages which need to be scanned for correct comments. More than 200 will end up in a "Request too long" error on most server configs.
So how do we solve this issue for our users? Bulk analyzing?
I found https://wordpress.org/plugins/wp-bulk-delete/ but I need to buy the Pro version to filter the comments. Deleting all comments is an easy task, but there could be valid comments in between ...
If people are not updating ASB they will end up with huge amounts of spam. In my case 20k+
Even with post per page set to 200 this will end up in 100 pages which need to be scanned for correct comments. More than 200 will end up in a "Request too long" error on most server configs.
So how do we solve this issue for our users? Bulk analyzing?
I found https://wordpress.org/plugins/wp-bulk-delete/ but I need to buy the Pro version to filter the comments. Deleting all comments is an easy task, but there could be valid comments in between ...