GM had and still has an impressive technical research center. Its just that establishment big companies dont get the respect that startup companies do. Nor can the employees win big like in a startup IPO.
General Electric is currently running a humorous TV commercial about this. A hipster engineers friends throw him a "new job party". But they go slackjaw when they discover he joinged GE instead of Facebook. GE has the oldest R&D lab in the country, started by Thomas Edison.