I totally support this feature. Groups have been forced to disable the ability to post on group walls because of these bots. Bots aren’t only the problem, you get some players spam the same message multiple times on the group wall and it is annoying for the groups staff to remove the duplicates. This has made the group wall an undesirable way to communicate due to spam and scam messages. Having this feature this will make managing the group wall a lot easier making the group wall a way to communicate once again.
To build upon what @buildthomas said and what the original post said. As well as removing all the posts with the same text you should be able to remove all the posts for a specific user. Currently the only way to remove posts by user is to kick that user out of the group and select the option, “Also delete all posts by this user”. I like the idea of only the owner of the group having this permission, however I fell the owner should be able to manually give certain users this permission as well. In other words this shouldn’t be a permission for a whole rank in the group only a manually given permission by the group owner.