Most of my life I've heard "older" people say, "You can't teach an old dog new tricks." I beg to differ.
At the age of 42 and after 20 years of service, I was laid off from where I worked. When I started my new job, I struggled to learn so many things as quickly as possible. Hey, I had to even learn where the restroom was and how to answer the phone. Every company has it's own way and system. What I found was that I could learn new stuff but had a problem forgetting the old. It would creep up at the strangest times. Like answering the phone. Once I answered with the old company's name and many times the old one would almost leave my lips.
So to me, learning new things is easy. It's all to do with the willingness to do so.
When it comes to my writing I believe the same to be true. No matter if you're a NYT best selling author, you can always learn something new, something to improve your writing one step higher than before, to keep you current.
A couple years ago, I read a book from an old favorite author. I was shocked to realize she wrote the same way she did twenty years ago. Maybe the book was one she had hid underneath her bed. Well, it should've stayed there.
We don't write like people did in the 1800's (Pride And Prejudice) and I'm glad. I like the action packed, highly emotional writing of the 2000's.