In January they said the virus doesn't transmit between humans. Then they said travel restrictions are xenophobic. Then they said the world should thank China for its efforts.
It sucks, but that's a problem with the UN, not with WHO specifically.
Unless you happen to live in one of a handful of central American, Caribbean or South American states which do recognise it.
It's a f*cking minefield, if you'll pardon the language, and I can't blame scientists who don't want to touch it with a fifty foot pole.
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.