Every year or so I make a folder in Downloads called “old” and put everything in there (including the “old” from the last time I did it).
When I find something I need in Downloads/old/old/older/old I am happy.
When I find something I need in Downloads/old/old/older/old I am happy.
mv Downloads old && mkdir Downloads && mv old Downloads
This is assuming there aren’t any special permissions/attributes on Downloads