What did they tell? It is frequently said that Taiwan sent an early email warning WHO about human-to-human transmission of what became known as SARS-CoV-2, and that the warning was ignored. This has been debunked and denied by Taiwan themselves[0]. On December 31, Taiwan and Wuhan Municipal Health Commission[1] both notified WHO about cases of pneumonia of unknown etymology[2], neither claiming human-to-human transmission.
That aside, I agree that a number of countries in East Asia, Taiwan included, fared much better than elsewhere in the world in terms of containing the spread of the virus.
[0] https://www.taipeitimes.com/News/front/archives/2020/04/12/2...
[1] https://www.who.int/news-room/detail/27-04-2020-who-timeline...
[2] Since WHO was contacted by both on the same day, it’s imaginable that Taiwan privately reached out to China first with “what’s that coming from Wuhan? we’re going international on this tomorrow”, putting the latter under pressure to report in order to save face. That would place Taiwan in good light even if human-to-human was not mentioned; unlikely to be substantiated though.
It doesn’t seem like “capable of containing a highly infectious disease” and “oppressive” go hand in hand.
They are far more capable of shutting new clusters down AND CONTROL IT. When we send people into quarantine in the West, we plea for them to stay home and everything is trust based because we want to keep our free society. Effectively, only very large local outbreak cases enjoy oversight by authorities.
Taiwan's pandemic game was on point before WHO finally let the rest of the world know about what has been suppressed in China for weeks if not months. Due to China's pressure they aren't part of WHO or UN and had no "official" global way to tell the rest of the world. They did, but were dismissed due to the massive hubris in the West and the geopolitical game China is playing.
SARS 1 is still on everyone's mind in Asia while many Americans outright deny Corona's existence even in July 2020. It's nuts.