In wrestling you get 2 points for a takedown, 1 point for an escape. I used to take guys down and let them back up all the time if they couldn't stop me.
While I agree that refs should be quicker to stand guys up if they arent working to improve their position (or pummelling faces), MMA is a sport were it is sometimes tough to see subtle things that are happening. I don't think one aspect is valued over another. If anything, it seems that Dana White would be incentivized to skew it towards striking. Knockouts sell.
Like Destino said, if you are at the top level of MMA, the UFC, you SHOULD train very hard to develop takedown defense. If you suck at it, then it is going to get exploited. That's what makes the sport great.