You can post all you want but they are American citizens. They have US passports, can travel to the US freely and if they reside in a state can vote for president ( obviously PR doesn’t have EC votes). Sounds like a citizen. In addition they do pay US taxes and contribute to the US treasury.
According to you so are Mexicans, people from Latin America, South America and Africa.
Please, don't educate me on Puerto Rico, as I work with a guy from there.