I always found it amazing that the guy who could be credited for the birth of rock'n'roll more than anyone else was still alive. Longevity isn't as much of a thing in the rock circles, and the genre has changed so much over time.
Also, major props for putting out a new studio album almost 40 years after his previous one.[1]
Chuck Berry and Elvis generally get the "King" label not because of the music they created, but because they achieved mainstream success with that music. They crossed the racial divide to bring music which had very much a black background (but also a white background) to the white youth of the day. Another artist which often gets the "King" label is Little Richard, but for the music rather than level of success.
Also, major props for putting out a new studio album almost 40 years after his previous one.[1]
[1]: https://en.wikipedia.org/wiki/Chuck_(Chuck_Berry_album)