Bologna--Baloney

Just why has the pronunciation of the sausage deviated so far from the pronunciation of the city it was named after?

Off hand, I'd say it's the palatal nasal, the weird (to anglophone eyes) orthography -gn-, and the tendency to reduce unstressed vowels (i.e., the first o) to schwa. It also helps that almost nobody spells bologna the sausage as Bologna the city. Also, a geminate palatal nasal is just too foreign an articulation for non-Italian speakers.

It's also funny that a dish of spaghetti with the eponymous sauce (or ragù) is called bolognese by almost everybody else but those in the States. Folks have been having trouble with the pronunciation of this northern Italian city for a long while: the Romans called it Bononia. The first n went through a process of dissimilation to become Modern Italian l.

Isn't the Italian gn the same sound as the Spanish Ñ? That's becoming common in the USA.

Isn't the Italian gn the same sound as the Spanish Ñ?

Yes, they're both palatal nasals.

That's becoming common in the USA.

Might be, but most US speakers pronounce canyon with an /nj/ instead of an /ɲ/: /'kænjən/ ~ /ka'ɲɔn/.