In recent decades, we've moved from decisionmaking by top-level individuals to decisionmaking by consensus. This usually results in lowest-common-denominator decisions: something that everyone can agree to. Bold ideas rarely survive a committee.
Also, consensus-based decisionmaking tends to squelch brilliant dissenters. It takes rare courage to insist that the majority is wrong. It could damage your career. Yet, if it weren't for brilliant dissenters, we'd likely still believe the world was flat and that incantations were the best cure for disease.
Alas, dissenters are as marginalized today as they were in medieval times. For example, we dismiss as "deniers" people who urge agnosticism on the Al Gore climate change scenario. We dub as "cynical" or even "racist," people who believe that education--even with continued increases in spending--won't significantly reduce the racial achievement gap.
All of us are shackled by conventional thinking's chains. When we hear a new idea from someone who strikes you as intelligent, it is important that we pull on ropes of restraint and give that idea a fair hearing.