No military in history since the invention of the airplane would go boots on the ground without first doing aerial bombardment.

Name any conflict in which the side going into a nation has aerial superiority that did not do aerial bombardment to soften the target before going boots on the ground to limit casualties on your side

It is absolutely naive and asinine to say they should have gone boots on the ground without doing any bombing whatsoever

As far as it being weaker I don't know if they're weaker I do believe they became complacent just like in many ways the US military has