I'm fine with spending tax money on energy related infrastructure and R&D. Probably OK with spending money on ancillary technology and sectors that are a dependency on moving towards a more robust future mix. As I've said earlier I'm completely agnostic about things like fuel types and whatnot, I just want it to meet our actual needs (not the needs the hard eco left wishes we had) and do so without being an eternal money sink. Supporting "green tech" that's not ready for the prime time is a great way to waste money. Imagine if we'd spent tons of money on 70s era photovoltaic with its poor efficiency? We'd be burdened now with that legacy tech and infrastructure that's basically worthless, the green energy equivalent of a nation full of landline POTS phone lines strung from telephone poles in a mobile phone age.
To me the bigger question is the "Climate Change" movement needs to resolve its varied factions that make any strategic progress and rational discussion impossible. At one end you have folks who seem to be keenly aware of the ROI involved in sustainable energy and the challenges and tradeoffs involved; perhaps willing to push the envelope on emerging tech but still grounded in reality. You seem to be in that camp.
Secondly you have those who seem completely unrealistic how they approach things. They handwave away concerns about NIMBYs or technology that's not ripe yet or willing to make the most ridiculous assumptions in pursuit of their goals. They make bold declarations like "of course we can be carbon free in 10 years" with no understanding of what's entailed or the costs. And they're completely ignorant of how it's all going to be executed or paid for.
And then you have those for whom "climate change" is merely a vehicle for seeking major economic change, whether that's soft democratic socialism or hard bolsheviks. The kind like Greta who talk about "the fairy tale of eternal growth" like the human mind has expended all the world-changing ideas the world will ever have and now it's just about dividing the pie. The ones who can't decide whether fighting climate change is goal #1, or "helping the poor" with policies that self-contradict ("let's reduce miles driven because it creates carbon, but let's increase bus service to poor neighborhoods even if the buses are empty 95% of the time" kinda stuff). Which of course makes any attempts at rational, economic and business sense discussions of alternatives impossible.
One other thing the "climate change" folks are going to need to accept is that resolving this would almost certainly involve making some rich people even richer which is going to be hard for the primarily left wing advocates of "climate change mitigation" to accept. Just as to get the railroads built we needed to offer land grants and such that created wealthy men, the idea that this will somehow only benefit the poors is a fairy tale that a lot of folks need to wake up from.
For me, and I can only speak for myself, I see this as a means to an end thing. I may be very far off into the deep end, climate nutter, etc, but I see this as a true end of humanity (or at least as we know it) scenario. If we are willing to spend tens of trillions of dollars stabilizing the ME in order to maintain our oil-based economy, we should be willing to spend tens of trillions to save the planet.
Now, as to your points above. We did spend tons of money on 70's era photovoltaics, and we've ended up with modern day solar panels. That doesn't mean you can just pitch money at the problem and it magically goes away, but you can put money to it and not outright deny the problem exists, as the current administration is doing.
Rational conversation is ending because the time for rational conversation is ending. Environmentalists have been sounding the horn for 50-odd years, and we're now starting to reap the results of inaction. You have segments of the planet that may be less than a decade away from becoming uninhabitable, and some of those places have billions of people. Inevitably you're going to see some fragmentation of approaches at this point, and some of those fragments are going to seem desperate (because they are). A fragment we haven't yet seen is the ignorant but desperate, that one's going to be messy.
I accept that some people may end up filthy rich as a result of these actions. I also accept that if we do nothing, some other fucks are going to end up filthy rich and living in a fallout shelter. So, whatever, some fuck other than me is going to be rich, but at least in one scenario my cousins and their kids still get to exist in the future.
Regarding NIMBYism, and how hard to push this? I say fuck it, if there was ever a case for eminent domain, this is probably it. Panels on every roof, paid for by the govt. 500kwh on every property that has the land to support it, paid for by the govt. Kick it up to 1kwh if 500 won't level us off on average yearly usage with roof panels + 500kwh on land alone. Moonshot that shit, employ the everyone, and make a statement to the world that the US isn't dying without a fight.
As for where it's coming from? For one, tear it from the military budget, they've got plenty to spare and half the places we're active in won't be inhabitable in 20y anyhow, so screw it. For two, track down the American dragons that have been sitting on fortunes and never make use of them. Mandate that shit goes somewhere (economy, govt, or philanthropy) or it gets utilized for a better purpose. Yes I know that's beyond socialism, I'm pretty far past the point of caring though.
I accept that most may not agree with me. Zero shits given, considering none of this will matter if we don't halt what's happening right now. There won't be anyone left to care.