You have any study to support your Hypothesis? Cuz as far as I'm concerned, limiting reentry with quarantine period set reduced the number of infected people infecting others. And for every one infected produce two more infections which produced four more which produced eight more etc... There could have easily been 200,000 deaths by now. But all you're doing is spouting your Hypothesis - literally flinging it at the wall like a piece of shit - with no data to support it.
Give me one piece of data that shows Trump's action to close off travel hurt us rather than helped us.
Trumps closing off China did help. But...
Federal closing off flights from China actually had much less effect due to "community infections" already planting the seeds.
Every little bit helped, but closing off China, only to let 40,000 Americans already in China return to the US was the proverbial screen doors on a submarine.