Someone..... somewhere.... can explain

Not really, but I can give you these takeaways:
a. Since "Memento", Nolan has been obsessed with the use of time flowing in his stories. "Memento" is a good thriller told backwards using the loss of memory as the mcguffin.
b. Nolan is obsessed with narrations that happen at the same time, creating certain parallels. He loves slowing and accelerating time for us to understand what he is telling us. "Inception", "Interstellar" and, in a way, "Insomnia" have these features. Note all films' titles start with "In".
c. "Dunkirk" is a set of three different stories told in three periods of time, A week, a day and an hour, that convolute into a final climax. Again, Nolan uses time itself as the mcguffin to make us interested.
d. "Tenet" doesn't slow or accelerate time, it just turns the story into a loop. Of course we will see errors and goofs and we will ask questions, and these questions won't stop, but when I saw this film I understood Nolan was making a story with no beginning and no end. In order for the story to be a loop, you have to travel backwards in time with a little help of sci-fi.

There are many, many YouTube videos explaining the meaning, plot etc in detail, been there ever since the movie came out.

The inconsistencies are huge, but didn't take away from the film for me.

The way an inverted person interacts with forward objects, or the way a forward person interacts with inverted objects is kinda disregarded except for a brief mention of "instinct." Logically, it doesn't quite work. But as a movie, it didn't bother me.

I think time-travel movies always have flaws. You just have to decide if you go with it or not.