He is not arguing, as many do, that we can no longer think straight because we do not talk proper.

= As many do, he is not arguing that we can no longer think straight because we do not talk proper.

参考译文：他并不像很多人认为的那样认为，我们由于不能好好说话进而不能再清楚地思考。 
备注：as many do (像很多人认为的那样)，,为as引导方式状语 ，do为替代词，替代argue=think。he为句子主语，is arguing为谓语动词that we....为谓语动词 is not arguing 的宾语从句，补齐调整语序后就是下面完整句子

As many argue【方式状语】，//he【主语】 is not arguing【谓语动词】 //that we can no longer think straight because we do not talk proper【宾语从句】.【备注：方式状语从句表示肯定含义(as many argue)，主句表示否定含义(he is not arguing)】

参考译文：像很多人认为那样，我们由于不能好好说话进而不能再清楚地思考,但他并不是这样认为的。

备注：即“主语he” 否定 “as many do”引导方式状语从句陈述的(因为“我们”说话不得体“我们”就不能再清楚地思考)观点。上面句子意思换一种说法就是下面句子。

Many people think that we can no longer think straight because we do not talk proper.But he doesn't think so .

很多人认为因为我们说话不得体进所以我们不能再清楚地思考,但他并不这样认为。