should we all play an instrument?

Yes, there are so many benefits that come with it

Increases memory leaving extra room for more educational things

The reason you can remember a lot more when playing an instrument is because theirs so much to remember like we're to place fingers or the pitch your instrument should be when playing a note and the remembering the notes places and how to play them

Is it popular?

Yes, it popular many people have played an instrument through out their life and many play an instrument almost their entire life