Tim touches on the biggest reason why there's usually no real R&D department1 in gamedev: it costs money, money that you're not immediately seeing back in an itemizable bullet point that you can sell to your money men, who are therefore absolutely not interested.
Among, you know, other things23.
1: Best you can do is get a Strike Team that usually works on something that comes from the production side in the first place
2: Like the fact that there seem to be a fuckton of people — in well, most jobs I guess, not just gamedev — that absolutely don't want to take responsibility or have initiative and forward momentum, and are really only there to Do What They're Told And Not A Dot More While They Draw A Steady Paycheck.
3: This would also require there not to be constant churn and pigeonholing of people into rigid roles, of course.