Why do domestic elites immigrate to the United States?

The United States is a western power and is at the leading level in the world in all aspects. It is natural to immigrate to America.

However, in recent years, the immigration threshold in the United States has been continuously improved. It's getting harder and harder to immigrate to America.

Looking around the world, Australia and the United States are comparable, and they also have a beautiful living environment and quality education. Why not immigrate to Australia?