It's more plausible that any company will give the more acceptable, easily digestible explanation, rather than the real one.
But really it's the politicians who won, first by banging their chests for all the investments and jobs they created, now for getting an easy out. They can't be blamed for not seeing through any ploy because they can argue Foxconn obviously had good intentions sabotaged by "a misunderstanding" that couldn't have been caught.
It's very unlikely (by that I mean close to impossible) that Foxconn just "blundered", went through many rounds of negotiations, and started building, while genuinely not being aware that the US labor market is different from the Chinese one.
Large companies are unlikely to ever tell the truth about their motivations, but they're even less likely to when they were doing something manipulative and dishonest, as Foxconn was here.
https://www.reuters.com/article/us-foxconn-wisconsin-exclusi...
He said the company was still evaluating options for Wisconsin, but cited the steep cost of making advanced TV screens in the United States, where labor expenses are comparatively high.
“In terms of TV, we have no place in the U.S.,” he said in an interview. “We can’t compete.”
Foxconn has factories in Mexico, Chennai, Malaysia etc. which produce a significant amount of devices but I doubt a factory in US will take off. This article from 2012 about the Steve Jobs "These jobs are not coming back" remark is probably still true: https://www.nytimes.com/2012/01/22/business/apple-america-an...