No-one and I mean NO-ONE, not even GOD is worth 2 million a year!
To give a specific example, I think David Beckham was.
When he moved from Manchester United to Real Madrid, something like £20-£30m of merchandising income went with him. It toppled Man U from being the highest earning club in the world that year, and passed the crown to Real.
So even without his undoubted talents on the field, he was worth something like £5-£10m a year just as a way of selling shirts.
Similarly, someone like Clarkson made the BBC an awful lot of money via Top Gear, before it all went titsup. As well as being entertaining to 7m Brits, and tens of millions more worldwide. And to prove Clarkson did have something to do with it, when they brought in Chris Evans, he couldn't make it work. I don't know how well the Matt LeBlanc led version has recovered.
To be fair to Evans his TFI Friday was a genuine cultural phenomenon back in the 90s. I hated it, but it was mandatory viewing amongst quite a bit chunk teens/twentysomethings. That is actually very hard to achieve, and so people who can manage it get very well paid by execs who can't, but are desperate for more of it.
So talent that is thought to genuinely attract ratings, and is considered hard (see risky) to replace, will get paid lots more. Whereas people who are doing a good job in a field where lots of others are also good will get less - as you can replace them. There are plenty of good political journalists, but not many people who can successfully host a Saturday Night entertainment show. And that's one of the holy grails of TV channel controllers. So people like Norton, or Ant & Dec get big money.