I certainly don't have enough information to say. As my picture shows, at least some of the states without a lock-down really don't need one because people are both isolated, and have little contact with people from outside. VietNam had fairly severe lock-downs, at least in the major cities, and I saw some headlines that
claimed they didn't have a single death. My understanding is that if you seemed sick, they put you in some sort of facility with other people.
As
@Everskyward said, another question is whether the shutdowns were worth it. We are only now starting to get reasonable information about how many were actually infected, and as that testing continues, we may find a lot of us were infected with few symptoms. It's possible the world over reacted because China, due to a lack of information, may have over-reacted. They did shut down their major holiday- the equivalent of Christmas and Thanksgiving here. The orders banning travel came down on 17th January in China. I do have a small window, as I work with a number of Chinese there (dealers and customers). Since there is so much travel there, many people were planning to leave Saturday, 18 Jan. My point is that many countries took notice of that, and also did the lock-down as the pandemic spread. These countries also didn't have the ability to see how many were actually infected.
At this point, it may be possible to say the lock-downs weren't needed
only with 20/20 hind-sight. What happens if the next one is more deadly?