I don't think it was the stock market that changed the rhetoric out of the orange house, those drops were expected and baked in. It absolutely was the bond market that changed the tone. Overnight, Treasury yields were going up when you would expect them to go down. When money moves out of the stock market, typically it would move towards Treasuries, the safest investment on the planet, which in turn would reduce yields. But in fact, Treasury yields were going up which suggests that not only was money moving out of US stock, but it was also moving out of US Treasuries. In short, foreign capital fleeing the US. My understanding was that bond yields in Europe were dropping suggesting at least some capital was landing there.
Was there a state actor pulling the strings, or multiple state actors working together to send a message to Trump that they are not without weapons and neither Trump nor the US is invulnerable. That would not surprise me. To the degree it was somewhat coordinated, it presumably would need to be state actors in order to mobilize enough volume to make a difference.
Just my 2 cents.