I had certainly noticed a few of those things.

The "ping" effect from Echoes is also used on Roger Waters' Amused To Death.

I've also noticed a few of the well known riffs from guitar solos on The Wall first appeared in Dave Gilmour's solo album a year or two earlier.

I guess once you find a sound effect that is really effective it is hard to use it just the once. I don't think there is any deeper meaning, or "intertextuality" as the academic world would call it.

Welcome to the site BTW.

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Can talk about wrong and right.
Of those that are forced to choose,
There's some who will choose to fight.