Because shielding is advice and you are implying otherwise, if you were to continue that line of thought what would be your next question?
"Should I tell everyone I know they are being illegal?"
"Should I berate them and barricade their door?"
"Should I report them to authorities for disciplining?"
Wind your neck in. If you are worried about your neighbour then offer to help, have a conversation and employ empathy not judgement - you are not the boss of them, you are not them and you have no idea what their situation is.