Here is one good article on "X weren't considered white" myth

https://www.washingtonpost.com/news/volokh-conspiracy/wp/2017/03/22/sorry-but-the-irish-were-always-white-and-so-were-the-italians-jews-and-so-on/

There is a lot more to say about this than I'm willing to write here so I'll just link this paper

https://sci-hub.se/http://www.journals.uchicago.edu/doi/abs/10.1086/666383

Second, no boundary separated SEEs[Southern & Eastern Europeans] from whites; SEEs were not widely recognized as nonwhite, nor was such a boundary institutionalized. In fact, where white was a meaningful category, SEEs were virtually always included within it. To be sure, a fairly bright boundary separated SEEs from northern and western Europeans (NWEs) for a time. This boundary was based on religion, national origin, citizenship status, and even intra-European racial categories. It was not, however, based on whiteness or non whiteness. ... The crucial point we emphasize, however, is that the SEE story suggests the remarkable stability of the white-nonwhite boundary, not, as is sometimes assumed, its fluidity.

This one looked at census classifications and found no evidence of this myth

https://digitalcommons.kennesaw.edu/cgi/viewcontent.cgi?article=1096&context=jpps

In this paper, we question the now widely held belief that some non-Anglo-Saxon European immigrant groups such as the Irish, Italians, and Jews became white in historical America. We have found no evidence to support the “becoming white” thesis in terms of change in the official racial classifications of these groups in the record of social institutions such as U.S. censuses, naturalization laws, and court cases. Non-Anglo-Saxon European groups arrived in America as whites, and there was no need for them to be reclassified as whites.

This paper found that 19% of male British immigrants married Irish wife and 15% of British female immigrants married Irish husband. Not exactly a behavior from people who supposedly consider Irish to be non-white or inferior

https://sci-hub.se/https://pubmed.ncbi.nlm.nih.gov/24259757/

As for Ben Franklin, the one quote he made about Germans you never find them citing is this one. Wonder why.

"Yet I am not for refusing entirely to admit them into our Colonies: all that seems to be necessary is, to distribute them more equally, mix them with the English, establish English Schools where they are now too thick settled, and take some care to prevent the practice lately fallen into by some of the Ship Owners, of sweeping the German Goals to make up the number of their Passengers. I say I am not against the Admission of Germans in general, for they have their Virtues, their industry and frugality is exemplary; They are excellent husbandmen and contribute greatly to the improvement of a Country."