That's the exact same thing you could say about corporations buying up food companies - that they have the resources, talent and infrastructure in place to improve the product.
Having more and more game studios owned by one of several giant corporations is not a good thing for consumers in the long term.
I would actually say in the food industry it works somewhat to the consumer's advantage, in the sense that most progress with food items comes down to scientific advancements. From the standpoint of shelf-stable mass production, one massive corporation with 10,000 scientists is typically going to be able to fund more research and make more progress than 10,000 mom&pop operations working from the back room of a restaurant. What you lose in variety of organizations, you gain in variety of organizational capability.
That said, there's a huge difference between food science and creating videogames. Innovative and creative approaches are extremely important in entertainment. This is less like the food industry and more like the music industry, where it is very clearly to the customer's benefit to have a large number of independent labels experimenting with different approaches.