Generally, the knight is more powerful early when there are lots of pieces on the board and diagonals for bishops are blocked. As the board clears, the bishop becomes more powerful.
Material count is very complicated. It depends heavily on the position, (as said by most people on this thread). Knights can jump over pieces and can change the colors of squares they attack. Therefore, they’re better in crowded positions. Bishops are limited to one color. Their value depends on how many pawns are on the color of the respective bishop. If you have seven pawns on black squares, your white bishop is better. (And also generally better than your knight.) If this doesn’t answer your question, feel free to message me with any confusion you might have regarding my post. Thanks! :)