We don’t know.
The US came back from a US president hiring private goons to spy on his political opponents.
The US came back from a US president illegally selling weapons to Iran to fund right wing militias in South America.
The US came back from a US cabinet member taking literal bribes from oil companies to give them oil drilling rights on federal land.
The US came back from a US president illegally firing a cabinet member and installing his own lackey.
But it didn’t HAVE to.
I don’t think there’s really such a thing as a ‘point of no return’ for a Democracy. But it is possible to get to a point after which you don’t return.
This is actually (spoilers for terrible movie Scales: Mermaids Are Real) the climax of the movie Scales. Mermaids can control water and their blood heals people in that movie, so hunters are trying to get their blood and then one guy tries a last ditch bad guy move and the main character pulls all the water out of his body and he horrifically melts.
Kind of made me side with the hunters at that point it’s a horrifying power.