You know, I'm still not quite sure why people always blame the parent company for buying and "ruining" a game development studio but never criticize the people responsible for selling, who usually then leave and form another studio. In most cases, it's not like that had to sell. They just saw dollar signs and lots of them. They picked money over controlling the future of their company. Do I blame them? No, not really, but I certainly think they bear as much responsibility for a studio's decline as anyone else. When you sell to an EA or an Activision, you know what might happen eventually.
Anyway, development studios rise and fall naturally as staff comes and goes. Many of the studios that have been around for a long time are no longer the same as they once were. It's not something I really stress about. The only real shame is when well-loved IP get mishandled or forgotten.