The premise of the film is intriguing. It is definitely worth a watch. However, the plot is far too complex to be weaved properly in a couple of hours. Almost everything---action sequences, dialogs etc---seems a little too hurried. We go to the movies to have a great experience. Nolan has always delivered great experiences---Inception and Dark Knight are nothing short of masterpieces. Tenet, however, falls short. There seems to be too many loose ends, and the expectation that the audience will brainstorm for days at end to figure things out isn't too reasonable. For a scientific film, the problem at hand should be well defined (for example, it was clear upfront what the problem was in Inception). I am still unclear what was the big problem that the protagonist was trying to solve in Tenet.
But still worth a watch.