Vietnam has a population 10 years younger than Taiwan / Sweden / Germany. This is a very significant factor when we are talking about Covid, and explains the very low mortality rate in Vietnam.
But yes: Vietnam still did great, most likely thanks to very early intervention (as early as January).
Vietnam has low mortality because they stopped the spread of the disease early on. If they had allowed it to sweep over the country, like Sweden, this population age difference might have been a factor. Thankfully, it never came to that.
But yes: Vietnam still did great, most likely thanks to very early intervention (as early as January).