Dear Gurudev, if one thinks that one’s Ishta(most revered deity) is the most superior, then does that not bring about fundamentalism?
See, if you ask any mother in the world, she will say her child is the best. There may be so many other children in the world, but for her, her child is the best of all.
Fundamentalism is considering or showing that others are wrong or lesser than you. However, having a feeling that my deity is the highest for me and your deity may be the highest for you, cannot be fundamentalism.