t_viktor212’s review published on Letterboxd:
1) it's probably the most confusing Nolan. There's much less exposition than Inception, so much is left at the viewer to figure out on his own, there's brief visual clues that help but don't really so much. You won't be able to understand everything a first view, mostly only the general plot.
2) it's very fast paced, which also makes you more confused about the plot. Audio mixing is similar to Dunkirk, very loud score and effects.
3) there's absolutely nothing wrong with the movie being too confusing. I've seen people giving lower ratings because of that. Remember, the ending of 2001: a space odyssey is also super enigmatic.