Unfortunately, a lot of people in the US are so lazy that they haven't stopped referring to all Spanish-speaking, dark-skinned people they see as "Mexicans". It doesn't matter if they're from Puerto Rico, Cuba or Guatemala.
Admittedly, I have been guilty of using the term Hispanic. I had a girlfriend who referred to herself and her family as Hispanic. Her family moved to Michigan from Mexico in the 1960s.
Thank you for sharing and spreading the word! ✌️