Yes, I think it's a native speaker of English, speaking so called Received Pronunciation. It's a very good model.
I agree. A clear speaker of BrE RP.
The /aʊ/ sound (among other things) reveal that it is not quite the 'refined' RP that was normal in BBC news and documentary programmes until well into the 1960's - and beyond: listen to David Attenbrough's accent in his well-known nature programmes. But, as BC says, it's a very good model - for formal situations in the BrE world. Among younger speakers, some might consider it a little 'posh.'