yeah but if you take the time to think about it for 5 seconds more it completely breaks down.
For example cars move by burning gasoline, creating energy which powers an engine that moves rods and axles. Its an application of entropy, you go from a more organized state - gasoline - to a more chaotic state - CO2 and heat. That is a forward movement in time.
If you REVERSED entropy and time, the car would just sit there as energy becomes more and more dense, ultimately collapsing into a black hole as energy density exceeds an atomic nucleus. You wouldn't run the car backwards, you'd just get a ton of micro black holes popping in every location you applied massive amounts of extra energy to reverse entropy.
Its not a big deal, thats what Nolan does in every movie - take a basic idea like "what if you could share dreams" or "what if black holes let you talk to yourself in the past" or "what if you could reverse time so future people could live on a planet without global warming" - and apply that at a personal level.
His other movies worked because the personal stuff was really interesting. In Tenet the personal stuff is drab and dull, I literally did not give a single fuck about a single character. All I knew was two dudes were super thirsty for a pretty skinny white bitch. Its supposed to be a movie about how our actions in the present are fucking over the future, but since we never really saw the effects on the world in the future even that was poorly done.