Absolutely, what Trump who calls himself a "stable genius" has inadvertently done is make a lot of people come out openly and on the record arguing for ethnic cleansing. It provides the answer to why Gaza was ultimately decimated and mostly destroyed.
In the excitement of getting something that factions of the Israeli government have argued for over decades, many supporters are openly coming out supporting the idea. When even Piers Morgan has to tell Alan Dershowitz (arguing that the Sudetenland displacement the 1930s was a good thing) reconsider the implications of what he is arguing for, there's a massive problem.
You are also right that it will be Israelis that ultimately pay. The reaction from MAGA has been surprising and extremely angry and emotional. Ranging from "I don't even like Palestinians but this is morally wrong" to "I didn't vote for this" and "No, more wars or money for Israel".
Trump has unwittingly provided the impetus for a coalition of different groups to unite against him.