Not just a screaming racist, but a rubbish historian, judging by his quote.
I mean, maybe there's some major missing context whereby he actually means something very different from the words he said.
But if not, well, whether it's slavery or Catholic emancipation, or independence of the America, or the Norman conquest come to that, history is not somehow "settled" when 200 years are past. It creates where we are today.
The irony of him positioning historical events as somehow finished with, while whining that statues to these events have been removed from where they were demanding the attention of the public in 2020...
NB I say this in case someone wants to argue that he should be free to express whatever political views he likes and still keep his job as a professional historian.
Like another David, Irving, he's shown he's actually pretty shit at doing history.