The weakness of no centralized hierarchy is endless divisions based on endless different interpretations of Scripture as the past few hundred years have shown.
And yet after 2 millennium we still see strong Bible based Evangelical churches sharing The Gospel. A decentralized congregational Christianity will always be overwhelmed by a politically connected centralized hierarchy, but the truth will still remain. In the end the Bible will supersede anything a centralized hierarchy can come up with.
China is terrified of the growing Evangelical Christianity in it's midst and as hard as they try they can't stop it's growth. The Gospel will always overpower institutional control.
The failure of the Pope to rein in the USCCB, not to mention Pelosi, et al, continuing to receive communion (even in the Vatican) indicates there is indeed a problem with hierarchy.