I can’t think of any economist that would argue that it’s desirable to produce everything we use within our own country. Maybe it’s better to make sleeping bags elsewhere.
In any event, my guess is that the cost of materials, not labor, is the determining factor. Supports for cotton farmers and other corporate welfare add enormously to costs.
If you accept the article as written, it looks like Exxel thinks it can compete if the Bangladeshis pay the 9%. If that’s the case, it’s likely that Exxel can produce sleeping bags much more efficiently than others.