The "tonight" becoming a calendar link feature has not been around for years, it's new to iOS 7.
No it isn't. I promise you. You may not have noticed it before or it may have been less widely implemented or whatever but that ability has been knocking around in IOS for years.
And if you're implying that Apple, even if they had a way of knowing for sure the exact number of people who used a certain feature, bases all or any of their arrogant and forceful design choices on the consumer's best interests/desires, that's absolutely ridiculous. They have proven time and again they don't care a bit and will do what they want. That is most people's biggest complaint about them as a company.
Chip on your shoulder much? You'd think they'd poked you in the eye rather than just had the "arrogance" to offer a feature that you don't personally happen to use.