This piece on Haitian immigration and US policy lays everything at the feet of American racism. It's pretty typical of Vox's journalism of finding an academic sympathetic to your position and then quoting that person exclusively.
First, yes, American policy towards Haiti has been steeped in racism since Haitian independence in 1803. American policymakers, especially in the South, were repelled by an independence movement made up of rebelling slaves, and America made active efforts to undermine Haiti throughout the 19th century.
However, there is a reason why America enforces its borders and there is a reason why America has been historically reluctant to admit large numbers of Haitian refugees.
First, every country enforces its borders. That's literally the definition of a state: an entity with sovereignty within its borders. This "open borders" bullshit is actually more politically inept a slogan than "defund the police." As the piece sort of notes, Mexico has a large detention center in the south of its country to detain migrants from Central America. This is, of course, laid at the feet of the US, because there is no reason for Mexico to want to enforce its own borders. And as we know Lopez Obrador is a lackey for the US. (Narrator: He is not, in fact, fond if the US.)
So, yes, America does not have to let anyone into its country that it does not want to let in. And, yes, America needs much better immigration LAWS to let more people in. It's inexcusable that the DREAMERs are still in limbo. We can and should be welcoming many more people from around the world who want to come and work in the US.
The interviewer makes the point that America accepts Cuban migrants and not Haitian migrants and posits that it's because of skin color (a lot of Cubans are what we would call black) and not because American immigration law was written to favor Cuban refugees from Castro's regime.
The reason why we have not been as accepting of Haitians has definite racist beliefs, but there is also the reality of Haiti itself. Haiti is the Western Hemisphere's poster child for failed statehood. As Guatemala becomes a nearly failed state, Colombia moves away from being a failed state. Meanwhile, for decade after decade, Haiti teeters constantly on the edge of state failure.
Naturally, for many people the fault lies with the incredibly wealthy nation to the north, based on the atrocious way Haiti was treated in the 19th century. The reality is that the "international community" (whatever that means) has made a large contributions to Haiti. After the 2010 earthquake, around $13B in aid money flowed to a country with an annual GDP of $14B. Haiti has been unable to create any sort of political stability that lasts for more than a few months here, maybe a year there.
If America opened its borders to Haitians, Haitians would flood the US. Their country is mired in cascading calamities of bad governance, ecological and geological disasters and a cycle of poverty that has proven impervious to outside efforts to help. This has led many people to say that the Global North is simply doing aid wrong, whereas it seems more likely that Haiti's problems cannot be solved by infusions of foreign cash and that it seems to reinforce Haiti's cycles of authoritarian rule.
America can have a better immigration policy towards Haitians. But that would require America to have a better immigration policy towards everyone, and that will not pass this Congress. The idea that America's legacy of racism is why we won't take more Haitians seems simplistic and deterministic. Too often, we blame circumstances on malevolent actions, when sometimes things are just shitty.
Things in Haiti are shitty. They have been a long, long time and they seem to get worse just as they try and get better. It's tragic. However, America is no longer trying to squash Haitian democracy the way we were 150 years ago. We would very much like a stable, democratic and prosperous Haiti and have tried to make that happen.
Our failure to do so has to be shared with Haiti. It's their country.
I hope we can find a way to make our immigration system more humane and accept more people via legal channels. But simply saying we should take in Haitians will only lead to more Haitians trying to reach this country without going through legal channels. So we are negotiating our way through an imperfect world with imperfect laws and systems. That's not exclusively some racist plot against Haitians.