This happens everyday, all day, on almost every major stock on the U.S. markets. Legal or not , spoofing is hard to prosecute and almost never is. Day traders often place large orders and wisely have to cancel them as the market moves against them. In any case with bitcoin this much ado about nothing and is really par for the course for trading on any major asset. In a robust market for cryptocurrencies, if bitcoin with a $60 B market cap can survive this "spoofing" , it will only get stronger in stability. Also, this is largely why Level II quotes became largely useless years ago in the markets, and clearly seeing the order book in cryptos has to be discounted in making trading decisions as well.
This is still a great post to raise awareness of the issue.