Immigration restrictions are not intrinsically racist. Every country, within its sovereignty, has the right to establish the restrictions of those who arrive, those who remain, and those who must leave. That is not a debate. What is debated is that all laws must be fundamental in human rights, love, compassion and respect for humanity.
But the fact is that the restriction side of US politics has historically revolved around racism and xenophobia and still does so today. President Trump is his most recent personification. Their comments of hatred, his lies and their violation of the basic human rights of immigrants show this.
It's not that there are too many immigrants, what is correct to say is that like president Trump, there are too many racists in the United States. Therefore, immigration laws that are not racist, ethnocentric and / or xenophobic can be approved.