You say that: “Broadly speaking blockchain only solves a singular problem: Trust.” but there is another equally significant contribution that deserves to be acknowledged: scarcity.

Bits & bytes can be cloned effortlessly by computers which is why a version of Photoshop ripped from a DVD is indistinguishable from the same version downloaded from a CDN as an iso. As long as the hashes match, you wont be able to tell apart the master copy from its 1000th copy.

For money to be valuable, in addition to trust, it also needs to be scarce in the physical sense. Blockchains allow us to engender that illusion of scarcity in the digital world, otherwise it would be impossible to tell apart the binary representation of a $10,000 currency note in one computer node from counterfeits held by other nodes in a network.