You are right, music is easier to remember. It makes me think about the ABC’s. I can recite the ABC’s without singing the song I learned as a child but I still hear it even as I “say” the letters.
I cannot recite the lyrics of the Star Bangled Banner but I can sing it, albeit off key :).
And speech has tonality, without it it’s flat and monotone and emotionless. Think of the early generation of computer generated speech, you can understand the words spoken but it certainly doesn’t sound human. Language without inflection, no matter how rudimentary, doesn’t convey anything but cold fact and even then it looses meaning in translation.
Isn’t music in some ways just an extension and exaggeration of speech?
It can be: some can speak in such a way. Much of what we call a 'good speech' is in delivery, which has to include rhythmic and tonal variation. Shakespeare should be done this way; the plays are written poetically which is no accident; he is still the Bard.