Darwinism is also full of "x happend differently than previously thought". Any theory is allowed an must adapt to new data. It's not like you're explaning a dozen of particles to which you add a new one every two decades or so. The domain of the theory shapes the theory.
Yes, scientific theories also adapt to new information. However, there's a substantial difference between this and what ID proponents engage in. The evolution (pun intended) of scientific theories involves saying "that was wrong before, here's what we think now" and the newly adapted theory is criticized and tested. Any scientific theory is falsifiable; even if not actually falsified, there's always some test that could, if it produced the appropriate results, disprove the theory.
Intelligent Design is just the God of the Gaps dressed up in scientific-sounding language. It collects the unanswered questions in biology and says, "We do not know how this happened, therefore an intelligence was involved." And of course if you dig deeply enough, "an intelligence" is almost always Yahweh, father of Jesus Christ, although they often try to keep that quiet in order to appear more objective.
There are two basic categories of contradictory facts for ID: there are things like the flaws we're talking about here, which say "this could not be intelligence" and there are direct attacks on the gaps, where unexplained things like the emergence of "irreducibly complex" features are explained naturalistically. Intelligent Design deals with both easily. The former can be dismissed by just saying that the intelligence wasn't involved in that particular bit. Or it can just be ignored, which seems to be the standard reaction. Any resource that discusses evolution will discuss unanswered questions and problems with the theory. Resources for intelligent design, as far as I can find, also discuss unanswered questions and problems with evolution but make no mention of any potential problems with ID. The latter can be dismissed by just moving on and continuing to object to other gaps. Or, as often happens, it can be dismissed by labeling the scientist as an anti-religious bigot.
There is literally no imaginable discovery that could overturn intelligent design. There are many imaginable discoveries that could overturn evolution. That's fundamentally what makes the latter scientific and the former not.
