gzip is 33 years old, tar is 47

Like pb and j, gzip and tar go together. Some questions:

Why didn't tar just grow an encryption feature? Why is being able to zip a new program?

Does any other common file format pairing combine extensions the way you do with .tar.gz or (sometimes) .tgz?

Why don't people do that with video files to show codec and container format?

https://redd.it/1uxpzy4
@r_linux