Hopefully, programmers have learned something about how to do things slightly better (or better matched to current needs) in the 40+ years since C was invented (or still decades for most other languages).
I just read an article about Swift. It said 11% of the top 100 apps use Swift. It didn't get into how old the apps were or when they started development, but at least points out the challenge about legacy code.
It is 100% swift. To stay on topic I'll say that removing for-next loops and ++ operators took me about 2 minutes tops. They really are not necessary. I am also trying to remove even for-each loops wherever I can replace them with map/filter/reduce.