The only enhancement I can think of is propagation for ever-higher frequencies (UV, X-Ray, etc), allowing more bandwidth. But realistically node hardware improvements regularly boost the performance of the same fiber cable, much like how cable modems are still improving using the same RG-6 from the 60's. (RG-6 is old, but it is still very good- physics still works just the same)
Last-mile power/sewage/data/etc hasn't changed much because it is fundamental. Water travels in pipes. Sewage also travels in pipes. The only reason data changed (POTS to cable/fiber) is because data was originally piggybacked on a network never designed for it.
One day we might do fiber optics with gamma rays, or invent wormhole communication, but I'm prepared to invest in plain-old visible-light fiber optics for now.
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As for water distribution in general (not last-mile), that's a problem with water rights, not water companies. It's a legal nightmare that has nothing to do with public vs. private utilities.
You could have said the same of steel if its quality had not improved, or airline travel if it had not gotten much cheaper, and become available to the masses. You are falling into the trap of only analyzing the 'seen', and failing to think of the 'unseen'.
>"The expensive part, which is the wire or fiber in the ground, hasn't changed materially in decades or more."
It will soon have to change if we are to have fibre on the last mile, and may change again when the technology evolves further; one of my concerns is that utilitization causes ossification, and prevents further progress, as is the case with the sewer, power, and water last miles.
>"Would you like to explain how a monopoly for-profit entity can be expected to do any better? Why would they care about droughts or abuse if it isn't costing them money?"
Thanks for setting up a false choice, I love those! I have no idea why there should be a monopoly on the purification and distribution of water.
Having private entities selling water would reduce the number of droughts, as they are likely to price according to volumetric use, and to price based on scarcity. Droughts are a problem of pricing, not of the scarcity of water; if you want a good example of how this is the case, motor vehicles never fall from the sky, and there is no shortage of them.
P.S. people are coming by and down-voting all my comments at once (I have gotten at least 25 down-votes here so far), could someone please let me know if I am being offensive, discriminatory, or going off-topic?