I have work to do and shouldn't be here. But here goes as to why it was a personal rant and not reporting of facts. What she said is as follows:
"“Dominic Cummings broke the rules."
Actually this is debatable, not factual. The rules were not to travel except for essential work, food or care-giving. He argues they were travelling to get care for their son. It also depends on whether they came into contact with anyone on their journey, or at Barnard Castle. Durham police have decided not to fine or prosecute so where is the factual basis for saying that he broke the rules?
"The country can see that, and it’s shocked the government cannot."
This is incorrect because 'the country' isn't in agreement. This is a persuasive technique which she's using to gain support for her argument. The very fact that she's using a persuasive technique indicates that this statement isn't factual. The word 'shocked' is emotive - again, this is a judgement by Maitlis and it isn't factual.
"He was the man, remember, who always got the public mood."
'The public mood' is a reference to Brexit and the Conservative win in December. 'Remember' is a personal appeal to the listener - another rhetorical technique, not a reporting of facts. She's reminding you that he's the guy responsible for Brexit and Boris as PM. If you hate both of those things, she is reminding you of reasons to hate Cummings. This is nothing to do with his journey to Durham.
"He tagged the lazy label of ‘elite’ on those who disagreed."
'lazy' is a personal judgement on the part of Maitlis. Again, not factual. Basically she is saying that if you didn't vote for Leave or the Conservatives, Cummings called you names. She is giving Remain and non-Conservative voters another reason to hate him. And this is NOTHING WHATSOEVER to do with the journey to Durham. Factual? Not a chance.
"He should understand that public mood now. One of fury, contempt and anguish.”"
'Should' is another value judgement by Maitlis. Not in the least bit factual. 'Fury, contempt and anguish' are personal opinions. They aren't factual because how do you measure fury, contempt and anguish? They are extreme adjectives, designed to persuade the listener. She's also adhering to the rhetorical 'rule of three' - she's a Cambridge literature graduate so she knows how to compose a persuasive piece better than anyone. But there are virtually no facts here.
Basically this is a diatribe against Cummings because he was the architect of Vote Leave. She's saying that if you voted Remain, remember that he's the guy responsible for Brexit. In the last sentence she repeats the phrase 'the public mood'. This is the mood which she previously stated was in favour of Brexit. It's an attempt to argue that even the public who voted Leave have turned against him. It's hyperbolic nonsense, in other words, and as far from fact as it's possible to get.