I am surprised “supposedly” did not make the list, along with “pacific” when people should say specific.
“along with “pacific” when people should say specific”
Might not be a mispronunciation, it might be a slip of the tongue or mondegreen (mistakenly using the wrong word).
There’s a tv show I watch where one character does that constantly, with some funny results, like “worst case Ontario” and “beauty is in the eye when you hold her”.