French people are known to pronounce FBI as English sound, but say CIA as 'Say Ee Ah.'
Now you can see that's even encoded in Google Translate here.
How did that happen ?
I tried Google Translate. For FBI it stated that it is an abbreviation and defined it as police. For CIA there was no information like that. My guess is that CIA is better known as a suffix than an abbreviation so it was pronounced as if it were a suffix.
In theory, the FBI is domestic only and the CIA is extraterritorial only (although there are items in the news every week that say otherwise) so maybe greater exposure is why we call the one agency the "fibbies" and they call the other "See Ya"
It makes me feel old to remember when both agencies were universally held in respect. Or gummint in general, for that matter.
Fairly old, as well your memory extra extraordinary.