GT2 RS will be very quick on the track, except it won't be half as good everywhere else, not to mention the 720S will have a spider variant that is exactly the same performance. When you need a hardcore track day car just to compete with the cruiser from other companies, let alone a convertible, then yes, you need to up your game if you really want to compete at that level.

Then again, maybe Porsche just don't care to compete with exotics. It's not their niche and it never has been. They do just fine with what they're doing. At the end of the day, they don't care about being the best, they care about making money.