The MAGA movement in the USA (~30%) has taken on a dangerous cult-like and fascist tendencies and ignore critical thinking, democracy, and facts, and instead glom onto a cult of personality. It’s not enough to believe 95% of what they (the cult) believe, it’s 100% or you will be excommunicated. It’s pretty scary times over here actually
Even if that's not the case, in many political races in the US, MAGA politics is the only option for conservative voters, even those who wouldn't consider themselves a part of the MAGA movement.
Of course, it's pretty messed up that the rationale to continue voting Republican is apparently, "well, I don't like Trump and dictators and the erosion of democratic values, but... man, that Biden guy annoys me".