There’s an African saying along the lines of: “Two bulls can’t stay in the same kraal/stable”.
Elon and Trump are both strong-willed and were therefore bound to clash.
For such personalities to mesh, one person has to be willing to admit wrongdoing, back down, and let the other one off, even if they know they are right and the other is wrong. But they both can’t and won’t. Hence the fallout.