It would have spread regardless.
What was the time period they waited? A week, two weeks? Trump was on record being completely dismissive of the virus initially, as were many of his supporters and Republican governors. He's criticized his own Infectious diseases czar, Anthony Fauci, multiple times over recommendations he made for SOP's AFTER the virus had been raging through the US for months.
China isn't to blame here - piss poor responses from the governments of multiple countries and the nature of COVID-19 meant it was a pandemic waiting to happen.
If anything, you could argue that better precautions should be taken to prevent Cross-Species Transmission, but outside of convincing hundreds of millions (if not billions) of people to change their eating or animal harvesting habits (exacerbated by a global population explosion) you're not really going to get very far with that. All it potentially takes is one individual, business, or market not following the proper precautions.
By focusing on blaming China, we're doing ourselves a disservice.
Ask yourself if it is reasonable to expect that a government would be able to identify and isolate a pathogen before it has had a chance to spread outside the country, when the symptoms are similar to the flu, incubation period can run into weeks, and many who are infected are asymptomatic.
Are you going to start treating everyone who shows up in a hospital with flu like symptoms as possibly having a new, highly contagious disease? Hell, if I was the first person infected, I wouldn't have even gone to the hospital if all I had were flu like symptoms, and probably infected everyone around me.