I have never heard anything else but S-Q-L, in multiple workplaces. What I was new to databases I started with the history lesson, but was quickly corrected to pronounce it S-Q-L.
I don't even know anymore, nor does anyone else I think
As an alternate datapoint, I've almost solely (by a 90% majority or more) heard "sequel" and "sequelite" (/'siː.kwəl/ and /'siː.kwəˌlaɪt/, respectively) across 12 years and 6 companies (from FAANG to YC startups in SF and NYC)
akavi|1 year ago