A block member feature would be good to have for online safey

A block feature would be useful for this sort of situation.

That said, by your own admission, your username is going to attract creeps.

Why not change it? While the word smut may have a technical definition that has nothing to do with pornography, that understanding of the word is not the common usage. The addition of 420 at the end of your username, which has strong associations with Marijuana, just adds to the appearance that you are looking for someone to party with.

You can stubbornly plant your feet and insist that reality conform to your wishes and suffer the consequences or you could just pick a less suggestive username.