This movie is def more enjoyable on rewatchs when you have a better idea of what's going on, but this is still easily bottom tier Nolan. For a movie where most of the dialogue is exposition, it is shockingly bad at actually delivering information clearly to the viewer so they can understand what's going on. Part of the fault here is, I think, Nolan's style of dialogue where everyone talks really fast and in a really flat tone of voice. In other Nolan flicks this wasn't much of a problem, but here it is since it doesn't give any time for the exposition the characters are spouting to sink in. The other part is that Nolan's writing is just kinda bad. He def needed a co-writer here.
And while Nolan has gotten better directing action sequences, he still struggles with them. It's telling that a setpiece that sounds insanely cool on paper (crashing a giant plane on a hangar) ends up being rather boring and plain looking due to the way the sequence was shot and edited. And that third act battle oooh boy, that shit was a complete mess. No sense of geography, what or who the Tenet guys are actually ahooting at, or what they are trying to accomplish moment to moment. Nolan desperately needs a second unit to direct action scenes, and his stubborn refusal to do so is beyond frustrating at this point.
All in all, if you get through the overly convoluted timey-wimey shenanigans, you're left with a rather dull Bond movie. And I was actually excited at the idea of a Nolan Bond movie. After Tenet, not so much anymore. :P
It's a damn shame because the core concept of the movie is really cool, but is kinda wasted here. I can only imagine what this movie could had been had it been written or directed by someone else.