The recent crypto-bloodbath, as you called it, had not only to do with the regulations in China, but also with some famous American blonde princess.
Read what I mean here:
How Paris Hilton nearly destroyed the cryptocurrency market!
P.S.: Of course this post is 100% serious!
P.S.2.0.: I don't think BTC is way bubbly. Like you hinted at, many ICOs may be way overvalued. However BTC grew relatively small in comparison!