Because of their high prices, competition naturally occurred in those international markets, which led to a downward pressure on USA product prices, and ultimately wages, and job offshoring.
Basically, the global economy is a cycle: the USA was, for the large part, first to benefit by selling "overpriced" (to other countries' standards) products, but markets have pushed those products out, before readmitting them at somewhat reduced prices.
It is to the benefit of the US production for wages and spending power to grow throughout the world, since that leads to increased exports at — now — affordable prices for the world! Heck, it's a tactic employed in both recent crises to get US products to sell (2008 and 2020, USD was at the lowest level compared to eg. EUR for a while): basically, by decreasing the international value of USD, you are increasing the spending power of other countries willing to buy US products.
The only thing uncertain is if we ever get to wage parity throughout the world (unlikely at 100%, but I think effects would be felt even at 50%), will we prosper or fall?
> I don’t accept the “we” here. Who did what exactly to “destroy” it?
Companies decided to outsource manufacturing jobs to third world countries and politicians accepted free trade in the name of some stupid theories about "greater wealth" creation, without pausing to think about a fairer distribution of that extra wealth. That led to stagnation of lower- and middle- middle class in the West while yielding vast gains to the rich Westerners and the newly middle-class people in developing countries.