Nah they were just occasionally lynched by xenophobic separatists. Just because you say something doesn’t mean it’s true. You can read all about our history of knee jerk fearmongers in the Library of Congress if you don’t have first gen immigrant friends//family as primary sources who you’re comfortable enough to converse with.
Attacks on Italians were not limited to the printed page, however. From the late 1880s, anti-immigrant societies sprang up around the country, and the Ku Klux Klan saw a spike in membership. Catholic churches and charities were vandalized and burned, and Italians attacked by mobs. In the 1890s alone, more than 20 Italians were lynched.
One of the bloodiest episodes took place in New Orleans in 1891. When the chief of police was found shot to death on the street one night, the mayor blamed "Sicilian gangsters" and rounded up more than 100 Sicilian Americans. Eventually, 19 were put on trial and, as the nation's Italian Americans watched nervously, were found not guilty for lack of evidence. Before they could be freed, however, a mob of 10,000 people, including many of New Orleans' most prominent citizens, broke into the jail. They dragged 11 Sicilians from their cells and lynched them, including two men jailed on other offenses.
Anti-immigrant sentiment continued until the 1920s, when severe restrictions on immigration were put into place by the U.S. Congress. When this legislation passed, the great era of Italian immigration came to an end.
https://www.loc.gov/classroom-materials/immigration/italian/under-attack/
Aa far as your response to the persons with the “illegal” grandfather from 1830: Duh, it’s apparent you don’t get humor.