I see you're one of those that doesn't know how the USA is designed. The states have to directly ask for assistance from the federal government in the correct way, or any assistance/interference by the federal government provides can result in a state suing the federal government for extortionate amounts of money, and the state would win. EVEN IF IT WOULD HELP PEOPLE!
Trump started out by saying that he could do nothing until the states requested it in the right way, and NO ONE CARED. It seems everyone thought it was a lie, or a trick, or something, or just completely forgot that he said that from the start. It doesn't matter what he said later, because IT'S NOT SOMETHING HE CAN CONTROL.
Panic is bad, and considering how much panic happened for the previous coronavirus outbreaks that did effectively nothing, it wasn't a bad descision except in hindsight.
That was all of the medical experts at the beginning of the outbreak, not just the politicians. Even Fauchi. You can probably find video of it if you're willing to dig through the shitstorm of anti-Trump propaganda it's now buried under.
Which cases are you speaking of specifically?
Nothing new there... It took FEMA several days to get WATER to the superdome. That's not nearly as difficult to do as ventilators and quarantine equipment.
Some people are stupid. They still vote though, so ignoring them as a demographic can spell doom for a campaign. Trump doesn't ignore them, and he's the first to really do so.
That said, the politicization happened equally coming from both political parties, and many independants all at once. It was politicized because of how the boatful of tourists was handled, and it escalated from there. It never should've been politicized like that, but it was. The media loved it. The more political and divisive, the more money the media makes, so they will gently twist the reporting to favor one side or the other for different meanings, which had a far bigger effect with this particular issue. Once they got a taste of it, they never let it go.