Given the number of politicians and media figures (who have influence over politicians) going along with the "no evidence" line early on, I believe the deleterious impact that I mentioned was real and significant.

That's only ~10% of the reason that people are critical of the WHO though. They also refused to declare a pandemic until until weeks after it had spread globally, even though early R estimates were around 3, which delayed countries' ability to respond quickly. They wouldn't recommend masks until months into the pandemic, even though similar viruses such as SARS were airborne.

The list of heinous mistakes is laundry-list long.