I was flying around an ocean to find an ocean monument, but instead found an area where all the chunks rendered very strangely. Each one seemed to render the same section in stacks as the screenshots show. They changed rapidly what was rendered even when paused. Approaching the area had no effect, neither did reloading the chunks with f3 + a or reloading the world. Logging out and back in again fixed the issue.
A large distorted entity was also visible in the area.

Unsure how to reproduce. Explore to find another area. It happened at (400, 150) on seed -3367407422388620531