Some people are like that, but some aren't. Some people are convinced to hate a group because of lies, propaganda and confirmation bias. When the lies start to be exposed, it can also start to unravel the hatred.

It can be difficult to expose lies in a way that is convincing, especially nowadays when media is so polarised, so people from another camp are likely to think you are lying if you challenge their existing beliefs. But this is obviously an example of people starting to realise they've been lied to nevertheless.