“The Horns of the Altar” and bulls?

[GrandizerII]

“On the day I punish Israel for her sins,
   I will destroy the altars of Bethel;
the horns of the altar will be cut off
   and fall to the ground.

As you say, it's probably a polemic against altars erected/readopted for other gods.

It's not about bulls or calves, no matter what connection you may have thought about with regards to these altars.

No connection even here?

“So the king fnconsulted, and he made two golden calves; and he said to fnthe people, “It is too much for you to go up to Jerusalem; behold your gods, Israel, that brought you up from the land of Egypt. And he set up one in Bethel, and the other he put in Dan.“ 1 Kings 12:28-29

Where's the connection in the text made between a golden calf and altar? I'm not seeing it.

Golden calves != altars (even per the Bible). Golden calves were representations of the other gods. Altars were where you sacrifice animals at for the gods. The corner horns of the altars in Exodus and elsewhere have nothing to do with the golden calves or calves/bulls perse (AFAIK). Rams had horns also, so do goats.

BTW: I'm just a layperson going by what he's reading, so a reminder to refer to scholars for the actual answers.