To add to that, the reason that the tilt is so important for life on Earth, is because the tilt causes the seasons. The seasonal variation of warmth from the s

To add to that, the reason that the tilt is so important for life on Earth, is because the tilt causes the seasons. The seasonal variation of warmth from the sun leads to differences in atmospheric and surface temperatures. The atmosphere warms faster than the oceans, creating a temperature gradient. This is the primarily mechanism that energises the water cycle. i.e. evaporation, cloud formation, rain, rivers etc.