But in terms of storytelling, it's incoherent, with the damn overlapping timelines and no attempt to show the events sequentially and how they mesh, or to create actual, you know, characters. For me, it's no masterpiece despite some great sequences, and I probably won't even recall much about it in a couple of years.
Exactly! But for me that's why I thought it was interesting. It actually played with the storytelling form. The diffuse narrative (which you call incoherent) I found refreshing and unusual and it kept me engaged. I get that people like to follow explicit primary characters in a liner fashion but sometimes you just want something different. I particularly found this agreeable when applied to a historic war movie since these films are usually sledgehammer obvious in every respect and milk all the obvious narrative and character tropes in showbiz. Nevertheless, it's pretty clear Dunkirk isn't for everyone and it certainly isn't a perfect movie.