YMB - // When these people do speeches outside of the public arena they are quite different especially if they avoid direct politics (they usually do). I remember hearing Red Ken once, he is actually an entertaining and captivating speaker. //
There is clearly a cachet for companies using politicians as speakers, hence the lucrative market tapped by each and every PM on ceasing to hold office, and quite a number of ex-MP's as well.
As a matter of course, all will have developed some level of skill as a public speaker, so it's not difficult to make the far less arduous journey from the House, to a smart hotel function room and a captive and friendly audience.
It must be a relief to trouser far in excess of an MP or even PM's salary for the equivalent time, and far less effort, I imagine Mr Sunak is looking forward to his time in the sun even as I type.