Who really knows? I can better remember details now to be able to write detailed descriptions. I just enjoy...
Definitely there is an element of that. If you keep a “dream journal”, and write down what you remember in the morning, you will soon find that you remember more details all the time.
I think it is because when you don’t do that, your brain dismisses the dreams as useless information, white noise, and just “deletes” them from your short term memory. If you start keeping track, your brain learns that the dream must have some value to you and stops doing that, or not as much.