People will worship anything but God.
The powerful tribe of ephraim were jealous that gideon has so much military glory with his mere 300 men, they wanted to be part of the glory. So the point that God chose a leader and army that was intentionally weak, to show that the victory was god’s was rather lost on them. They worshipped their own ego and arrogance.
Gideon refused to be made king, the people wanted him to have the glory. He took some gold from victory and made an ephod, priestly item showing dedication to God, instead. So his family worshipped that object. It became a snare to them, the commentary sadly notes.
He died a hero, but the people quickly reverted to worshipping baal. They had learned nothing.
Even as he pursued the remnant of the army he defeated, his own people would not help him. It’s an incredibly sad chapter with harshness and faithlessness everywhere.
Yahweh was not concrete, not an observable object. Not tangible. The OT is all about the power of the true God, which is not an idol. It would culminate in god being made flesh so he had a tangible form. Jesus, God who walked this earth.
And it’s still true. Even after entering our world as a tangible figure in history, people will worship anything but God.