Most of his "controversies" would not even be news in the US. A person on a humorous show cracking a racial/ethnic joke is on TV every night.
We have nothing like OFCOM where you could actually get in trouble with the government for being highly offensive either.
And celebrities behaving badly is typical, so assaulting someone probably wouldn't lead to any major public outcry for his firing. It's not as though Sean Penn has trouble finding work.