The tweet was different though (and AFAIK, much earlier): "Preliminary investigations conducted by the Chinese authorities have found no clear evidence of human-to-human transmission of the novel #coronavirus (2019-nCoV) identified in #Wuhan, #China."

It clearly mentions that they're relaying what Chinese authorities are saying.

If you read e.g. https://www.washingtonpost.com/politics/2020/04/09/trump-vs-... the timeline of things is quite different than what you state.

I also don't see how this influenced anything. It took almost every country way too long to respond. Loads of countries thought it'll be fine for them.