The problem is that the example you are looking for is based on your own personal, subjective belief about what Black Panther was trying to say and who it was targeting. So, if I point out the vast majority of movies have mostly white casts, white directors, and white writers, you would probably respond with something like "But they aren't pandering to white nationalists/conservatives/whatever ideology you want to throw out."
I agree that having such a large degree of black representation in the movie was made a big deal and helped bump its popularity. However, the reason it was such a big deal is that that sort of representation had been absent in the super-hero genre prior to Black Panther. It's similar to Wonder Woman; that was a super hero movie with a female lead and female director, as well as much greater than usual female representation among the actors. In both cases, it is only because that sort of representation didn't exist that such a big deal was made of it. As such, the idea that the pandering of Black Panther to blacks would make tons of money if only it were done to whites is, IMO, asinine. Movies in general have been pandering in that way since the beginning.
And if you want a movie that panders to conservatives, with a mostly white cast, white writer, white director, how about Unplanned? That's an anti-abortion movie, it seems to be almost entirely white, and it was profitable. It doesn't come anywhere vaguely near the level of Black Panther, though, so I'm not sure about the idea that pandering to a conservative, white audience is leaving untold billions on the table is in any way supported by the example.
Red Dawn was a good example, and also nowhere vaguely close to as successful as Black Panther.
Here, have a couple of lists of particularly patriotic American movies.
The 25 Most Awesomely American Movies to Watch on July 4
The Most Patriotic Movies of All Time
Of course you might disagree with some of the choices (I did), but is that not enough patriotic American pandering to entice the many viewers you seem to think are avoiding seeing movies? Or was that sort of pandering used in the past, but not in more recent years?