That's not hard if they flag your node and all nodes connected to you. They can simply block you and anyone connected to you. The only way to get unblocked is to disconnect from you
Flagging doesn't stop commerce. What you're describing would require that an enforcement agent be able to stop a Bitcoin transaction, which isn't realistic.
I have tried opening channels with nodes that refused me. If I spammed it sometimes I could get one. They were automatically closed almost immediately. One used all of my liquidity first 😂 Stopping transaction on #bitcoin is impossible. Stopping people from transacting on lightning is very easy