So, I'm wondering, is there any language that has recently (say, ~1000 years) developed complex grammar not present in its ancestor language?
I am asking for recent changes because I can imagine that mass media (I can even imagine mass media in 1016 AD) somehow prevent this process.
I'm familiar a bit with a history of Indo-European languages and they all start with overwhelmingly complex grammar (I am talking about all that inflection of PIE) and then they get rid of it. For instance, English, but also both German and Russian have way less complex grammar than that of Latin, and Latin was there like 2000 years ago.
Not precisely related observation is that if someone tells you there is a language with 70+ consonants, you can be sure that the language is from Africa or Polynesian islands or suchlike, and the fact is that the language has been probably only recently exposed to civilization.
It's very easy to get a notion that languages tend to become simpler (say, simpler to learn) with time.