Hmm. So my question was "How do you conclude that paying by use is not going to be a good deal?" and you quoted by fixed cost observation back at me without making any additional argument.

To interpret this charitably, I guess you may be trying to say that it is still a good deal for people who drive a lot in any case and don't mind the fixed cost? I agree, but I think these people are going to be a shrinking segment, in contrast to your claim that it will "never" be a good deal for the consumer.

To reiterate, many people don't want to invest this fixed cost and drive everywhere, but once they have committed to the fixed cost, it's uneconomical to do the daily life the carless way.

All this is in the context of the necessary reduction of private car usage, considering the need recuce CO2 emissions. (Electric cars only cut car lifetime emissions to half, which is still unsustainable).

That's assuming no cost for parking which is a correct assumption if you are commuting from a suburban house to a suburban office park. But if you are commuting from a SF/NYC apartment to a SF/NYC downtown office and you want parking in both places then its safe to add a cost of $150 per month for each which is about $3600 for parking. Its all about context.

The obvious question is how would those numbers change with a shared car. It's quite possible it could be cheaper for many even with a higher per mile cost.