We reject foolish traditions such as series order. Next time we're bringing back 15 via time machine, then maybe we'll do an earlier one
Actually it's just that we did the most recent one to test the waters so to speak. As the stories are independent of each other it made sense to release the most recent first.
Wots3 is better than 4 in some regards. It allows a more open style of branching since it had the old UNSHEA5H at absolutely any time system instead of more limited one in 4.
Hell you could change endings as they happened with it. Moreover I belive it had the silent protagonist route.