It appears you are right. Conifers and other gymnosperms are totally outside the definition of fruit and cannot have fruit by definition. The seed cone is however an analog of a fruit for the gymnosperms. It doesn’t have to do with petals however. Lots of flowering plants don’t have petals. Example are these wheat flowers. You have to cut up the plant to even see the flower.
A pine cone is a fruit?
I was taught a pine cone was a “naked flower”, as it never developed petals and ovary developed directly and bore the seed.
It appears you are right. Conifers and other gymnosperms are totally outside the definition of fruit and cannot have fruit by definition. The seed cone is however an analog of a fruit for the gymnosperms. It doesn’t have to do with petals however. Lots of flowering plants don’t have petals. Example are these wheat flowers. You have to cut up the plant to even see the flower.