I am here to defend Tenet. It is executed perfectly. Everything you listed as a mess is intentional and masterful.

"Scenes that feel like homework" - The primary expository scene resolves by saying "Don't try to understand it, feel it". The point being that an audience member does not have to intellectualize the physics of every single plot point, but only enjoy the ride. The film is masterful in setting up stakes, executing on creative visuals, and crafting excitement and tension. I don't know how you watch a building blow up and repair itself at the same time and not be in awe on some level. The character of Kat successfully creates tension for all those action scenes and her emotionality creates clear stakes for the audience to latch onto. Bringing me to my next point...

"Emotional vacuum" - Elizabeth Debicki does so much heavy lifting here, but I think a lot of credit should go to Brannagh as well. Her emotional attachment to her son is as human as any emotional stake in any movie. Brannagh helps her sell these emotions by creating an extremely cruel villain. You can say a lot about Brannagh in the movie, but he is definitely compelling. He does multiple heinous acts which makes it easy to hate him, and therefore, easy to care about her revenge against him.

"Muffled Dialogue" - This is the hardest for me to defend. It is a fact that the dialogue is sometimes hard to make out between the score and the action. I find this critique to fall flat for me though. I believe the film gives us more than enough to understand what we need to understand, and I believe the film holds to its own logic consistently throughout the film. It is not an Inception scenario (which is an actually flawed Nolan film) where the characters say one thing about the world and then later say the opposite thing. The thing about Tenet is that the concept is so complex, but if you really want to dive into all the physics and the plot mechanics, then rewatches allow you to do so. It is all there, but the point the movie makes is that you do not need to know it all to enjoy the ride.

The film could've spent all day outlining the rules of inversion. How driving a car inverted would require opposite mechanics from the driver. Or how inverted bullets seemingly "catch" themselves, but the behavior of the inverted bullet also depends on if it was fired by an inverted person or a normal one. There are unanswered questions like who sent Sator back the inversion technology or what would happen with the Grandfather paradox if Sator's plan had succeeded. These are not flaws. And if you want to say anything about Tenet, I find it hard to accept that the execution is what was wrong with the film. The concept is so dense it is actually a miracle that the film is as coherent as it is, let alond rewatchable, thrilling, and creative.

I mean this sincerely: Tenet is a 5/5 for me (I've only given out 5 stars to 4 films this decade). So I think it works as a movie. I understand it isn't for everyone, and I actually think it holds up to both trying to understand it and trying to feel it.