Children do outgrow the need to have a daily nap. The question is, when do we stop insisting that they have one?
Invariably it's not black and white. Some days they don't seem to need one and others they obviously do need that nap to help keep everyone happy in the house! At our house we never stopped nap time. It developed into quiet time. When our kids said they weren't tired they were allowed to "read" (picture books are fine) in bed. They just had to rest in bed. It was their choice to read, look out the window, daydream or fall asleep. Note: Screen time was never part of quiet time. It's not restful!
Quiet time only stopped when homework and school activities took over. However, the habit is still there. Our 18- and 20-year-olds still will initiate their own quiet time to go read a book.