From your own link:
"Edward Alden, a senior fellow at the Council on Foreign Relations, says anxiety over trade deals has grown because wages haven’t kept pace with labor productivity while income inequality has risen. To some extent, he says, trade deals have hastened the pace of these changes".
The fact that "most estimates conclude that the deal had a modest but positive impact on U.S. GDP of less than 0.5 percent" (from your link) is largely irrelevant when most people do not get to see the benefits. Indeed, median American income has been shrinking since the late 1990s (when adjusted for inflation) even while the mean has increased.
Don't get me wrong. I'm one of the people who has done well out of the whole arrangement. But I totally appreciate others have not and are angry about it.