Is it rude to tell a person to shut up or is that a thing now?

both. the internet allows people to say that without getting their teeth knocked down to their colon.

[sep]IDC if I don't want to hear someone blathering like a fool I just tune them out.

Some people need to hear it!

When someone tells me to shut up. It's not an insult. It's just they don't want to hear what I have to say. Even though I'm always right. Hey if they want to be wrong that's their business.lol

Sometimes I tell people to shut up

In some cases it's necessary.