I don't understand what this means "It doesn't seem possible for Spacex to revolutionize the world, change it: sure they do...for 20+ years but they fail to rev

I don't understand what this means "It doesn't seem possible for Spacex to revolutionize the world, change it: sure they do...for 20+ years but they fail to revolutionize for 20+ years.And the reasons are obvious." Please explain.