Deleting a claim does not erase all record of it. For those who were already members of the discussion when the claim was deleted it will continue to appear, greyed out, until they acknowledge the deletion by interacting with the deleted claim; or marking the relevant branch as read (see: Marking a Branch Seen). Users with notifications relating to the deleted claim will still see them.
You can see all deleted claims in a discussion in their locations by opening the Discussion Menu and selecting ‘Show Deleted’. When ‘Show Deleted’ has been selected, you will see deleted claims in your search results (see: Finding a Claim).
For information on how to erase a deleted claim entirely, see Expunging a Claim.