An idea is a peculiar thing for a story. It’s just a seed. What grows from that seed is up to the creator. It could be a line of dialogue, a scene, or perhaps a whole premise. This is why if you hand two different writers the same idea you will get two completely different responses. It’s also interesting, as an audience, to compare the two and see which one took the right approach. A great example of this are the movies Doctor Strange and Tenet, both of which utilize the idea of reversing time in two completely different fashions.
The idea goes beyond simple time travel, though. It focuses on having time play out in two directions at once. In simple terms, it means having characters move through time going forward while characters (and objects) around them move through time backwards. For Tenet, this represented the entire premise of the film. The story is built around this idea and everything from character arcs, to setting, to the main plot revolves around the concept. In Doctor Strange, however, this idea is merely used as a plot device during the movie’s climax. The film technique is isolated to a single scene and used a single time.
While the merits of both films in their entirety can be debated, it would seem as if the idea of moving backwards through time was better handled in Doctor Strange. The reason: the idea itself is just too complex to build a film around. From a technical standpoint, Tenet probably pulled off the concept correctly, but since it stretched it out for the entire length of the movie, it could easily be confusing for the audience. Many people would have to watch the film several times to fully grasp the intricacies of the backwards time mechanism. That same device can be just as confusing in Doctor Strange, but since it’s just a single scene, viewers don’t have to extend themselves too far to understand the ramifications of moving backwards through time. The moral of the story: sometimes good ideas are best in small doses.