I'm sure there is if people like you go around refusing to let people in, yes.
Why should he let people in when it's his right of way since he is in the correct lane ? not his fault at all...
You're supposed to let people through/in/out or whatever if it's safe to do so and you're comfortable to do so. What is safe and comfortable about letting someone in just because they almost slammed into your side? Don't let those people in and let them stay in the right lane and have to go all the way round the roundabout again and get into lane ON TIME tbh.