Assuredly wrong on both counts. The second point is the more important one: The same companies that control the energy supply chain of the world today can afford, and are spending money on, lots of researchers and engineers (and M&A activities) to make sure those same companies continue to own the energy supply chain of the future, regardless of whether it's solar, hydrogen, nuclear or ethically sourced unicorn manure. Sure, in the meantime they will continue to hype their _existing_ tech because there's a lot of sunk cost there and the more feedstock you can flow through that infrastructure, the better the amortization looks. But if you think Exxon or BP has their neck chained to liquid dinosaur to the extent that they will become bit players in the future, you're totally wrong.
As for the two decades thing, that's a spitball that way misses the mark. We could start by pointing out that the average age of consumer vehicles on the US market (and the US is a big market, whatever Europe or other blocs choose to do) is 12.5 years and rising, so even if ICE sales were banned it would be way more than 20 years before they were insignificant. But consumer vehicles are only a slice of the pie, not the whole pie. The US military runs on oil. Replacing every vehicle in US military inventory (even if it's possible) is a very long term project. And that's not even counting shipping and civilian aviation.
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