Question

But all this does is to lower you to that same negative leve

Answer 1

分析一下句子,你就明白了：

But all（主语） this does（省略了引导词的定语从句,修饰all） is（谓语） to lower you to that same negative level（不定式短语作表语）.

具体的翻译要根据上下文了.