A major article of faith on the left is that bad things happen just because, they're not the fault of a specific person or belief, they just happen and no other belief system would do any better.
Trump is showing the decay of America is a choice. That there are better paths forward. That the glorious liberal "utopia*" is not, in fact, the ultimate end all final form of governance and the end of history.
That is why they get so pissed when he cleans up the pool. Because by cleaning up the pool he shows the pool doesn't have to be a disgusting rotting mess. And by showing it doesn't have to be that way he shows that it was that way because that's the end result of liberalism and liberal policies.
They'd rather the pool be rotting or even destroyed than people realize there's a better way forward than listening to them.
This is also how they can show a picture of a happy family from the 1950s and they HAVE to insist "oh no they're really FUCKING MISERABLE and all have SSRI-enabled mental illnesses and are all fucking each other in the ASS secretly, trust us, they were just as fucked up as we are but it's all propaganda hiding it!" Because culture, family life, and everything else has decayed significantly since then, and the major change has been the left taking ever more power in the US since 1960, and thus there are only two conclusions: Either the past wasn't better, or the left's influence on things isn't an unassailable good.
