Both these methods of deleting photos are very obscure and maybe both need to be changed.
Maybe change that “i” which implies information to a settings type icon, at least to we English-speakers.
Definitely need to add text to the edit page because that is the most obvious place users may go to delete the page.
A third option (which I don’t like and I think is too much work) would be to add “Edit Photos” to the dropdown next to “Edit”.
I notice this came up before.
https://forum.inaturalist.org/t/deleting-photos-from-an-observation/6787
https://forum.inaturalist.org/t/removing-individual-photos-from-an-observation-how/2117