While I agree that most would have been addressed under warranty, there are many variables and different driving conditions where the problem may not yet have surfaced. Low mileage, babied, garage queens come to mind.
It's just something to consider. Although the OPs started threads 5-7 years ago, the discussions do continue through 2020-2021 in some of the threads. Have to consider that active participating traffic on the forums have decreased significantly in the last 5 years.
Nissan replacing the entire trans was their way of addressing it even if it wasn't absolutely necessary. If out of warranty, it's not the end of the world and trans replacement might not be necessary. Shep sells the seals to address the leaks and, from what I understand, the process isn't that invasive.