There were many problems around these old crowns including: the color of the front teeth doesn't match, the cavities at the gumline, dark lines around the edges of the crowns and the edges of the front teeth are too short.
After
You can see now how much younger this smile looks. It still has a natural appearance. Notice how there are no dark lines at the gumline anymore. Notice that the porcelain work, really looks like teeth. This requires proper design at the start.