Look at the past and present greats of MMA, Georges St. Pierre, Randy Couture, Brock Lesnar, Dan Henderson, Tito Ortiz, Matt Hughes, etc. What do they all have in common? They all have solid wrestling backrounds which they carried in to there MMA careers.
A good strong wrestler can take you down almost at will. Once they take you down they can go from a north south position to a full mount in seconds. Having a feared takedown and ground game helps you in the standup because good muay thai practitioners or good kickboxers are going to be tenitive to strike because the have to be ready to sprawl the takedown attempt, and being tenitive in a fight is the worst thing you can do in a fight. When being a good strong wrestler, you can positition yourself to rain down elbows and punches without the other fighter being able to stop you.
When Travis Lutter and Anderson Silva fought, Silva was the heavy favorite because of his excellent muay thai and bjj. But even though he lost in the end, Lutter took down the #1 ranked pound for pound fighter and gave him plenty of trouble before being caught in a triangle choke. All the good wrestlers may not be always the funnest to watch because most of the action is on the ground and usally the fight ends in a decision, but the fact that they are so domitate, it doesn't matter how entertaining it is.
In the clinch, wrestlers can take you down almost instantly, and to a muay thai fighter like Anderson Silva, that is leathal. The only way to beat a wrestler is to keep your distance and to stay on your feet which is easier said then done. Georges St. Pierre vs Tiago Alves is a perfect example of how hard it is facing a solid wrestler when you are a solid striker.
So until there is a new discovery on how to beat a wrestler, the Matt Hughes' of the world will dominate MMA.