https://www.cato.org/blog/founding-fathers-favored-liberal-immigration-system
Alexander Hamilton argued that the “advantage of encouraging foreigners was obvious and admitted,” asserting that “persons in Europe of moderate fortunes will be fond of coming here where they will be on a level with the first Citizens.”
Father of the Constitution James Madison “was not averse to some restrictions on this subject, but could never agree to the proposed amendment” in part “because it will discourage the most desirable class of people from emigrating to the U.S.” In other words, not only were the Founders opposed to restricting the free movement of people into the United States, but they opposed restrictions on citizenship that they felt would discourage immigrants from using that freedom. Madison spoke of “great numbers” who would wish to come to the United States.