the amount of cryptocurrency they send to their potential victims is usually so small that sometimes, its hard to notice, but the main goal or purpose of the scammer sending this is to try to trick as many that will notice the transaction, into revealing their private keys, or trick them into visiting a malicious website.
The actual reason for the dusting attack is a threat to the address owner's privacy and FYI receiving some coins whether it dust amount of huge amount has no security concerns so you do no need to worry about the remaining coins in the address or wallet. But if you don't want to compromise privacy then you should freeze that particular UTXO or if the address has no other transactions then freezing the entire address is more than enough so the scammer will never be able to link the funds to any of your addresses.