Yup, it looks like the Gulf is a special case, as the waters are warm and the continual natural oil seepage over the eons has made for especially voracious oil-chomping bacteria.
And yes, the Gulf recovered amazingly fast from the IXTOC I blowout in ‘79. Not much in the way of chest-beating theatrics as I recall, as Mexico made plain from the start it wasn’t going to pay a dime in compensation to anyone.
I never even heard of Ixtoc 1 until this well blew out. If it made the news back in ‘79 I must have been on a TV hiatus or something.