He doesn't want anyone to know what he and his 'pals' actually get up to.
Perhaps, AI, if used properly, would be programmed (developed, whatever the correct term) to spot criminal activity.
Now, AI would never have gone to Eton (or any other institution with an old boys network) and would be unable to tell the 'real' crims from the privileged toffs (or American billionaires) and would treat them all the same.
I have no idea if AI can be 'corrupted'. I know feck all about AI except what I've seen in films and that rarely ends well, but if the likes of Johnson are worried about it then it just might be a good thing.