Support for Trump, or even Republicans writ large, means support for reducing taxes (both estate and income) on the wealthy, while increasing them on consumers (via tariffs). Musk has been an ardent supporter of Trump.
While I don't disagree with your conclusion, this line of reasoning makes no sense in a two party state where each party offers a menu of positions. Supporters are forced to make tradeoffs and pretending otherwise just gives you an incoherent picture of reality.
"Two party state" as in a government where politics are bifurcated. In a one party state, a citizen's voting history isn't informative whatsoever about their beliefs. In a direct democracy, their votes give you a complete map of the positions on any issue that came up. In the US, we only know that an R voter prefers the entire set of R policies over the entire set of D policies. Maybe they're pro-taxes, pro-welfare, anti-immigrant, pro-life, and pro-gun, and they weight these positions such that it makes sense to sacrifice the taxes and welfare to get the rest. So, while the party is anti-taxes, everyone who supports it may not be.