So now the trust devolves onto the designers of the Bitcoin protocol, the software programmers implementing said protocol, the programmers implementing the operating system kernel that said software runs on, etc. etc. etc.

Just ask the MtGox users about how completely ironclad that trust is. Sure, "transaction malleability" was identified in 2011, but that didn't help the users of MtGox, and the other exchanges had to take corrective action in 2014 as well.

If anything Bitcoin is even worse for the normal user; physical security is much much easier for most of us to grasp and implement. Is Aunt Tillie going to be able to ensure that she never gets too rich, so as to entice a cyberattack to steal all her Bitcoin wealth?