No, that's not the fundamental cause of hurricanes.

The fundamental cause of hurricanes is the difference between water and air temperatures. If both go up together nothing changes.

The difference is measured from absolute zero, so if both go up 1 degree there is actually even less of a difference than there was before.

Since the water is warm, and the air cold, and every model shows water temperature rise lagging air temperature rise, global warming should cause less hurricanes.

The higher intensity might be because the water would become warmer, and air temperature is not a constant. If a hurricane should happen to form when it's cold out, it'll be somewhat more powerful.