There should be multiple words for it. They call it a "risk" because it's not known with absolute certainty that it's not harming anybody, not because it's proved to be doing so or there's even a mechanistic reason to think it is (again, the evidence on tolerable upper limits for these things are very weak).
Compare to something like environmental ionizing radiation which is a risk period, because it works in a highly stochastic way and it has no real benefit (aside from xrays for imaging etc.) there is a certain probability of a certain number of people developing cancer. The risk can be so low as to not be worth worrying about, but it is objectively introducing some risk (even if just the risk introduced by the radioactive potassium in your average banana).
What this is doing is in no way known of quantitatively analyzed like that. We have basically no data and that's not a good reason to stop doing something that has known benefits like fortifying food. From what I saw they don't make any recommendations to stop doing it, they're just saying it's worth doing more research to find out. The most strongly worded part was with respect to children, and there I actually agree because of the amounts of cereal some kids eat.
And like I said, this is for the general population. I'd bet you that if we asked them if they think this applies to vegans and vegetarians too given potentially higher need and lower dietary consumption they'd say it's more likely to be that in that sub-population the risk/benefit is more in line with zinc.
Should we email them to settle this?
Absolutely there is -- in mega-doses. The mega-doses that a lot of supplement brands sell shouldn't be considered "safe" in the sense that the benefit side of the risk-benefit analysis is absolutely lacking. There's no reason somebody would need to take 1,000% of RDI of iron or most other vitamins and minerals. It's so much overkill that the additional 800% or so is totally pointless, and the "unknown risk" becomes meaningful.
Most multivitamin/mineral supplements aren't mega-doses if simply because that would make them horse pills and the consumer has trouble swallowing them (literally).