When you stop and think about it, when folk say (and most of us can be guilty of doing it) that such and such a person would sort the country out and/or make a great PM, in most of not all cases, no they wouldn't.
I heard someone say on tv the other day 'Nigel (Farage) would get the country sorted out, he'd make a great PM.'
Nigel Farage, or any of others people mention, could be parachuted in to be PM as of midnight tonight and he'd face the same challenges that all PMs face. I suspect even someone like Nigel, or heaven forbid Tommy, would realise it's not quite as straightforward or black and white to implement changes as they like to make out.
These talking heads are great at pontificating what should be done. Implementing stuff when you're the person/team actually responsible is rarely as straightforward. Back seat drivers and all that ...