We should select comparisons aimed at the getting the best result, not to make things easy on ourselves:
What if the Europeans had thought: “Hmm. The natives are following a procedure we don’t understand with regard to casava. Their explanation doesn’t make sense according to our own outlook, but it is apparent that they have a lot of experience. It may pay to be prudent rather than disregarding their rituals as superstitions.”
Had the Europeans taken this attitude, they may have discovered the toxicity of yucca, experimented with imitating the leaching procedure or, at least, have introduced it slowly, since reliance on a monoculture exposes a population to other risks as well. In either case, wouldn’t the Africans likely have been better off?
In case this seems like a special case, consider the impact of the introduction of potatoes to Ireland. As for the long-term, unquantifiable dangers of introducing genetically modified species into the environment on a massive scale; only time will tell.