I never suggested that it was perfectly fine for them to rely on the AI.
But you are presenting this as though it is an either/or question: either they use AI or they use traditional keys.
It isn’t. Having the CV suggestions doesn’t preclude students from using a key. Nor does using a key prevent them from seeing what the CV suggests and thinking about whether they agree with the suggestions or not. The two tools are complementary, not mutually exclusive. My point was precisely that – given a situation where it seems likely they will be using AI anyway, whether or not it is allowed, which seems to be your main concern – requiring them to critically engage with the CV suggestions will also require them to first acquire the skills to make identifications using conventional techniques. In other words, completely preventing them from using AI may not be feasible, so it may be more productive to acknowledge that it probably cannot be taken out of the picture entirely and figure out ways to make sure that they learn the lesson that you want them to learn in spite of the existence of AI tools.
Even if iNat had a “no CV mode”, this would surely not prevent students from switching back to standard mode, or using the demo CV, or some other image recognition program such as Google lens. If you want to reduce the likelihood that they use AI in any form to complete the assignment, then probably a non-internet-based option (i.e., not using iNat, but having them hand in their assignments in some other format, such as submitting a physical notebook or a Word file with the photo and their ID and notes) would provide the best chances of this. However, this would not prevent them from using some AI image recognition tool if they were determined to cheat. So even if you want the students to not use AI, ignoring its existence does not seem like it is an effective way to get the results you want.
If the point of the lesson is to get them to learn to use traditional keys and demonstrate that they have done so, then require them to cite sources and explain their process. If they rely on iNat’s CV instead of doing the work themselves, they won’t be able to complete this part of the assignment.