I live near the Amish, they are going to make it. Yes life will be harder for them, but they are prepared for a breakdown in civilization.
As others have pointed out, it may be more difficult for a single individual to make it, but a large family or small community has a decent shot of survival.
Amish are testing their resilience daily.
Like, there are a whole lot of reasons the article listed for why this won’t work in the future. You can’t just negate them because it works now.
It’s not just a breakdown in civilization - it’s a dramatically changed and broken planet in this scenario. The Amish will starve just as fast as anyone else when crops fail or it doesn’t rain for years on end.
Their predisposition for non-violence may change when they encounter roving gangs of wasteland bandits (from New Jersey) venturing about but that's not guaranteed.
They aim for it, certainly. They're quite likely to have good relations with their neighbors who are less restrained or forgiving, and who value the company of the Amish and other neighbors.