It's not most probably legal it is legal but the press have an agenda over morality and won't let go.
I personally have less of an issue with this sort of thing than others but I do understand the anger it riles in others my main problem is that the anger stems from jealousy in the main, the I deserve more for nothing brigade. Would love to meet a die hard lefty who has managed to build up his/her own business and then been lucky enough to sell it for a considerable sum of money and HASN'T taken exit planning advice to mitigate tax. Morally that's exactly the same scenario as here but why wouldn't you want to keep money that you have earned right? Anyway...
The problem is the hypocrisy. You're right, he hasn't done anything illegal but then again, I'm not sure Jimmy Carr had either. Can't wait for his next monologue on the issue!!!