The problem is that their agents/managers have put them in crummy movies lately. Actors act, they get offered scripts for movies with big payments associated. Sometimes they have to take roles in movies just to pay the bills.
Matt Damon, Vince Vaughn, Adam Sandler, are not good actors. I have never seen an Adam Sandler movie that I thought was funny. Matt Damon is annoying. Vince Vaughn is the same character in every movie.
George Clooney is also a good actor, but many of his movie are just too slow. He is in a lot of chick flicks. He was very good in “The Descendants”.
Tom Cruise needs to stop making action movies. He is too old. The last good movie he made was the one where he played a contract killer. I can not remember the name.
Depp is best in quirky roles like Ed Wood.