I keep a small solar/crank generator/USB-powered radio in my car. Which can provide USB power, act as a light, and also, in a pinch, charge my cellphone. You can get these starting at about $13 on Amazon.
That's not quite as good as having one with everyone, but as long as you're within walking distance of your car, you can probably get to it. It also has some benefits:
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More power-friendly than a cell phone.
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At least a portion of the kinds of things that might take out the cell infrastructure (e.g. cyberwarfare targeting the cell system) may also take out phones themselves, like if someone can push bad updates out to the phones. Your dead-simple FM radio isn't going to have problems unless actual FM radio broadcasters get knocked out. If you're in the US, there is very little real opportunity for someone to conduct a significant, conventional attack on the country, but being able to find holes in the Internet-connected infrastructure and do damage there has a lot more unknowns and the ability of various parties to disable or destroy it is much more of a possibility. Militaries do build up collections of holes to hit adversaries with. One of the first things Russia did when invading Ukraine was to knock out Viasat infrastructure, using a hole that they'd discovered in that company's network, to degrade communications in Ukraine by pushing out an update to brick satellite modems. I also remember some guy at a think tank in the US that covers cyberwarfare saying that one of the surprises was that Russia didn't try to disable Ukraine's cell network, either via cyberwarfare or via conventional means; taking out the cell network would do a lot to dick up a country.