The UK's culture on this stuff has been relatively famous since Orwell coined the term thoughtcrime. The major advantage the US has over the UK historically has been the oceans, but an interesting secondary one is the US was built by people who seemed to have a healthy fear of the extended groupthink sessions that the UK tends to fall into. It's always been something of a problem given how insular their upper class is.

The UK was an amazing leader on liberty in the days when absolute monarchies were the assumed default government, but their free speech standards are a long way from exemplary in modern times.