Once you start to do transactions that involve transfer of anything off-blockchain (ie. any really useful transaction) you still have the same issues with trust

Once you start to do transactions that involve transfer of anything off-blockchain (ie. any really useful transaction) you still have the same issues with trust and credit as without blockchain or whatever. What blockchain solves is somewhat fast settlement of monetary-ish transfers, which to me looks like a problem that does not really exist. (In my exerience SEPA transfers are mostly instantenuous and generally irreversible)