The cedilla originated in Spain, in fact its name means “little Z” in Old Spanish because it was a tiny Z you wrote under the C. Words that would have been spelled with Ç are usually just spelled with a Z in modern Spanish though. When and why it fell out of favour there but not in the other languages I don’t know the exact circumstances of.
Edit: What I can add however is that in modern Spanish the sounds for Z and the soft C are the same in the standard language and most dialects. That means there would be no distinction between the syllables za and ça for example, leaving the Ç unnecessary since you can just use Z instead. In some of the other languages you mention there may still be, or was when their spelling got standardised, a difference between C and Z which would leave the Ç useful.
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