Fear and hatred are powerful emotions that cause most humans' higher reasoning to shut off. Right wing media has been peddling both for over a half century. So yes, a significant fraction of the Republican voting base are ignorant (maybe not stupid so much as generally misinformed) and racist (at least to the point that openly racist rhetoric is not disqualifying in primaries/elections). Additionally, a large part of the base has proven itself quite gullible with regards to conspiracy theories and other (generally quite obvious) disinformation, especially when they play on existing fears/biases (e.g., schools turning their kids trans).
That isn't to say that Democrat voters are perfect, either. There's certainly a significant undercurrent of left-wing media that is built on fear and hatred - one only need to see how well conditioned women are nowadays to believe that every man they see wants to harm/rape them or how men spending time around children are presumed pedophiles - but it's not quite as prevalent and certainly not as targeted at political affiliation.
It's completely fair to point out that Democrats often fail to address issues facing average people, or when they do, it's done poorly. That's sad, and it needs to change. However, where I get confused is how Republican policy almost universally harms the average person, and yet they get a free pass, even to the degree that I've seen a large cohort of people blame the Democrats for failing to save them from a bad Republican policy/action without passing any of the blame to the Republicans that passed it (e.g., tariffs, DOGE cuts, etc.).
It pains me to see the anemic Democrat response to some of the batshit insane stuff the Republicans do (especially now), but I fear it's largely because the Democratic party is just as much owned and operated by moneyed interests. While the Republicans are stabbing us to death, the best we can hope from the Democrats is to put down the knife without providing any bandages.