How many of those were born in CH?
How many people born in CH never become Swiss? Because for the US, that number is ~0%.
And before you say: "well the US have different rules", well, ok, but then don't compare us to the US on the other number either, compare us to other EU countries with similar types of rules but different implementations.
CH has stricter naturalization laws than many EU countries and CH has mandatory military service which discourages many males from naturalizing, even those born in the country.