From what I've seen from Trump supporters on NextDoor you are missing a lot of cases where it is hard to come up with a good explanation that doesn't involve some stupidity or at least willful ignorance.
For example I've seen people saying they were going to vote for him because he'll stop undocumented immigrants from eating pets in Springfield OH. No one has been able to find any evidence of that.
There are also the people who say they will vote for him because he promises to get rid of some specific government service or program, and it turns out from their other comments that this is a service or program that they depend on but don't realize it is the same program.
Going the other way, there are people on NextDoor who I've suspected were a bit stupid long before I saw them in any political discussion. E.g., people going on about contrails being the government spraying us with chemicals or the new electric meters rolled out in this area over the last few years will make us sick because of their remote read capabilities (but the ones they replaced were also remote read--apparently they never noticed that they never saw a meter reader in all the years they had it).
Whenever one of those people later posted something that did say how they would vote it almost invariably was for Trump, and it would be for reasons like the ones above.
This suggests that while there might be reasons for a non-stupid person to vote for Trump, he also captured a big fraction of the votes of stupid people. That I think is one of the biggest difference between Trump and other candidates from both parties. Trump might be the first to actively court the stupid vote.
NextDoor is an...interesting...place from which to select a sample of voters. There are plenty of stupid people to go around, and Trump certainly doesn't have a monopoly on them--I would argue that the Left's appeals to various identity voters are also explicitly courting stupid people, they're just insulated by being members of protected classes.
The example you gave is an interesting one, because it's a situation where a very real concern--the public resources of small communities being stretched beyond their limits because the federal government refuses to enforce immigration law--was deflected by the media to something ridiculous. ("Brown people are invading our towns and eating our cats!") People voted for Trump because they saw through that kind of tactic, and they're far from stupid for doing so.
How the heck was that deflection by the media? Trump said live on national television "In Springfield, they’re eating the dogs, the people that came in, they’re eating the cats. They’re eating the pets of the people that live there".
Vance did later admit that this was just a rumor, and then encouraged people the keep on spreading it.
BTW, the immigrants in Springfield are there legally, which is another thing Trump has repeatedly lied about.
The big thing though is that they people I'm talking about who base their support of Trump on things like the eating pets things live in areas where there are not many immigrants (legal or illegal). They personally are not seeing any problems immigrant related.
All their information on this comes from Trump. And most of their information on every other issue. And even if they finally are convinced that he lied on something they never question anything else and go try to verify it.
And that's why I would consider them to be not quite up to par in the thinking department.
For example I've seen people saying they were going to vote for him because he'll stop undocumented immigrants from eating pets in Springfield OH. No one has been able to find any evidence of that.
There are also the people who say they will vote for him because he promises to get rid of some specific government service or program, and it turns out from their other comments that this is a service or program that they depend on but don't realize it is the same program.
Going the other way, there are people on NextDoor who I've suspected were a bit stupid long before I saw them in any political discussion. E.g., people going on about contrails being the government spraying us with chemicals or the new electric meters rolled out in this area over the last few years will make us sick because of their remote read capabilities (but the ones they replaced were also remote read--apparently they never noticed that they never saw a meter reader in all the years they had it).
Whenever one of those people later posted something that did say how they would vote it almost invariably was for Trump, and it would be for reasons like the ones above.
This suggests that while there might be reasons for a non-stupid person to vote for Trump, he also captured a big fraction of the votes of stupid people. That I think is one of the biggest difference between Trump and other candidates from both parties. Trump might be the first to actively court the stupid vote.