I'd say all of Europe, and America benefited from trade with developing countries, especially in terms of Energy. But then the definition of exploitation gets a lot trickier than it already is.

I believe exploitation is simply a not so useful label. Trade agreements, even those that appear lopsided, are in my opinion not morally wrong. The moral issues arise from accompanying violence, corruption and theft.

The developing countries who arguably have been "exploited" could not have developed even to their current state on their own. At least not within centuries.

The oil-rich countries in the middle east couldn't have used their oil for anything until they got the technology to get it out of the earth and somebody paid them for exporting it.

Same goes for many exports of African countries.

Sure thing, the "first world" has done a lot of wrong to the "third world". But the latter isn't going to get anywhere without help from the former, either.