Those people and that dynamic existed before Trump. He just did the cookie trick to tap the pool of disaffected citizens as a voting resource. But you are right, it’s that context that allows someone like Trump to rise.
I think the why to that is as simple as this:
New census population projections confirm the importance of racial minorities as the primary demographic engine of the nation’s future growth, countering an aging, slow-growing and soon to be declining white population. The new statistics project that the nation will become “minority white” in 2045.
The shift is the result of two trends. First, between 2018 and 2060, gains will continue in the combined racial minority populations, growing by 74 percent. Second, during this time frame, the aging white population will see a modest immediate gain through 2024, and then experience a long-term decline through 2060, a consequence of more deaths than births (see Figure 2).
https://www.brookings.edu/articles/the-us-will-become-minority-white-in-2045-census-projects/
There is a reason conservatives are conducting themselves like it’s win in 2024 or die. Because if your goal is to enshrine minority rule for whites beyond when they become a voting minority, 2024 is the last best chance you have to do it. From this point forward, whites comprise less and less of the voting population.
These numbers started emerging in 2012 after the 2010 census. In 2014/2015 Trump began his political rise. Those were also the years you saw conservatives like Jeff Flake start to opt out of future plans of the Republican Party because they were exposed to some abhorrent strategy, and when a cozy relationship between certain people in the GOP and Russia started surfacing. Why?
Maybe it’s because Russia needed to neutralize the US as an opposition to their goals in Europe, and conservatives needed the tutelage from experts in consolidating power in a way impervious to democratic elections. No direct evidence, but it explains a lot that is otherwise inexplicable.