Homomorphic encryption is interesting from a mathematics perspective, but in practical terms it seems like an awful lot of effort being invested to move even more computing off of your own devices and onto the "cloud."
Add a cryptocurrency wallet for which the signing keys are the private keys, and now it’s more like an immortal, non-subpoena-able corporation executing your desires using its treasury assets. (Which can include hiring real people to do real-world things, and even—given that you could provision crypto mining capacity—making income to keep said corporation’s actions [relatively] self-sustaining.)
But seriously while amazing in potential, having semi-intelligent contracts running around indefinitely would eventually have to cause havoc. Either by the “Paperip Maximizer” effect [1] or just having a huge weight dragging down the economy from accruing smart contracts.
But, assuming that one does, ever, want someone else to do a proprietary computation on one's data, it'd be real nice if that didn't require giving up plaintext.