It's worth remembering that evolution doesn't select for the best as much as it selects against the worst.
The reason we have such sensitivity doesn't have to be particularly game changing as long as it doesn't make us less likely to reproduce.
You can plainly see our big niche adaptations being used everyday. We think good. We recognize patterns. We use tools. We walk a lot, efficiently and upright. We communicate with high precision. We have a surprisingly efficient digestive system.
We're not busting out the ability to smell rain super often, which hints that it might be more in the "doesn't hurt" category instead of being a big advantage.
My guess is that being able to smell disturbed soil is helpful for tracking, either where an animal has run or where something has been buried. Our ancestors were not above digging up a fresh-ish dead animal a canine had buried for later.
But it could just be that rain sense slightly more accurate than looking towards the horizon was as useful then as it is now: vaguely, I guess? It just doesn't hurt anything.
Well yeah. That's the entire point of tax incentives and all that. We want them to do something so we make it in their financial best interest for it to happen.
In this case, we made it so their interests were best served by spending an ass load of money on research and development to make EVs more broadly producible. If you yoink the rule that made them do that away, it's not that they've wasted or lost that investment, but producers who weren't bound by those rules are at a comparative advantage because they weren't set back by the rules, and now they can continue to sell cheaper, dirtier cars for less than the bigger companies can sell clean or dirty cars.
It's to the advantage of Tesla because reducing the sales of electric vehicles while there's rising consumer demand makes it easier for them to sell cars at the same price with less competition.
It's worse for the environment but "giving a shit about the planet" isn't on the table in the current political environment. The most we can hope for is "the interests of a large company are tangentially aligned with those of the environment for once" and just run with it.