[delusional]

The Postal service is a utility competing on efficiency and price. That's not what "tech unicorns" get billion dollar valuations to compete on. Tech is about building a "platform" to siphon off money for all eternity while doing little of the ongoing labor of delivering or producing the value. To build that platform you need a moat, because otherwise somebody will come in a compete on price, so you build brand loyalty by gate-keeping the quality of stuff on your platform. That way any competing platform will initially be primarily populated by all the stores too "bad" to be marketed with the incumbent.

It's quite simply not financially lucrative enough to run a utility for venture capitalists. In a more sane, less inflated economic climate, this might change.