1- It’s factually correct, hacking & spying is illegal. It can land a hacker serious jail time, regardless of how morally good their intentions are, and regardless of how morally bad the people being hacked are.
2- You can interpret the disclaimer as a warning to other vigilante hackers wanting to do good. Think of it not as that Jim is being vilified, but it’s a message to you to be careful.
3- Think of it as a standard disclaimer, like you see on many products you buy. It could be a liability concern for the BBC to report on vigilante hacking against scammers if they were judged by the UK government to be glorifying and encouraging hacking.
Let the fact that they’re reporting on this story and showing the videos and shaming the scammers speak for itself and outweigh the annoying disclaimer.