What Was the Sin of the Golden Calf?

ASKING THE IMPORTANT QUESTIONS: What Was the Sin of the Golden Calf? (Prof. Joel Baden, TheTorah.com)

Many scholars, traditional and academic, believe it was worship of another god, the first commandment in the Decalogue, but what Aaron actually claims about the calf points to a different collection of laws.

I agree that it is clear that the golden calf was a representation YHWH and has something to do with Jeroboam's cult at Bethel and Dan. But what exactly the objection was is less clear. My late teacher Frank Moore Cross thought that the issue was iconographic: YHWH was supposed to be portrayed as enthroned above two cherubim, not two bulls.