I've come across this discussion in my own life, but seldom does it seem to be addressed on a larger scale. "Portuguese" does not fit into the same category as "Hispanic"-even though the very word comes from Hispanola-the name for the Iberian Peninsula in Roman times.
A very interesting article can be found here, about historical treatment of the Portuguese in a society of clearly identifiable races, and how the races are stacked against each other: http://www.researchjournal.yourislandroutes.com/2016/07/caucasian-but-not-white-race-and-the-portuguese-in-hawaii/
It covers the variety of definitions used officially, and the most defining factor: skin color. An "Olive Complexion" can be a flattering descriptor, OR it can be a way to define a version of race-without calling it out directly.
An interesting quote: "The Portuguese fell somewhere in between. Their wages were set lower than White Caucasians but higher than Asians and Latinos. They could not hold upper management positions, but they could work in supervisory positions."
Portuguese workers fell/fall(?) into an in-between category, which does not allow them to fully "pass" nor does it release them from discrimination. For those who imagine that American issues are divided into black and white, be advised that historically, and even now, there is a scale that is always being adjusted.
Language, accent, economic status, culture-and background are ways to assess how "American" someone is. Even Tom Brokaw has said that "Hispanics should work harder at assimilation," but he has since apologized for his comments. https://www.nytimes.com/2019/01/28/business/media/tom-brokaw-hispanics-assimilation.html
At what point IS someone/a group considered assimilated? When THEY can begin to discriminate?