I think it is as well. I really really wish someone would take up investigating this behavior because it affects all us normies without enterprise SSDs.
Here’s a very poor attempt at documenting this phenomenon:
The decay only affects cells that were written to many months ago, and weren’t updated by garbage collection, trim or the user. Garbage collection could fix the issue if it went over all occupied NAND cells, but it doesn’t do this on consumer NVMe. A deliberate rewrite of NAND cells will fix the degradation though, as evidenced in the linked post.