There is a huge literature in both linguistics and anthropology that indicates the feedback loop between language and cultural norms.

One simple example is the subject/object distinction in mainly Western as opposed to Asian languages. This creates inescapably different world views. If you cannot speak an Asian language (from childhood}, you can never be Asian.

But even when syntactic structures are similar, the primary difference stands. I was born an English speaker; I can never be a German.

No value judgement is implied in the hypothesis. There are no simple languages because there are no simple cultures. To a large degree, language is culture. Determining which culture is better is a matter of prejudice, not scientific inquiry.