My Prius gets 50 mpg on long highway trips, and those are the only trips I use it for. I think the Volt gets around 35 mpg when it's burning gas. I drive my Roadster whenever I'm not taking a long trip. That's why I say the Volt is the worst of both worlds. As an EV it is inferior to a Tesla, and as a gas car it's inferior to a Prius. It's a good fit for one-car households that normally drive short distances but need to make the occasional road trip. But most households in the U.S. have more than one car. A Tesla, or even a Leaf is perfect for all but long trips, and a Prius is more efficient for those long trips.
A Bolt would be a step down from my Roadster. A Volt would burn more gas on long trips than the Prius and is inferior to the Roadster for all trips under about 245 miles. I would probably not buy a Prius today, but in 2004 you could not buy an EV. And in fact, in 2004 EVs were not even on my radar. It was the Prius that gave me the bug for an EV. When the Prius shut off its engine and drove for short distances on electric, that's what made me want an electric car, and led me to buy the Zap Xebra (which at that time was the only EV I could get that was not a NEV). And I know other folks whose first taste of electric driving was when their Prius went into electric mode.