They explicitly say in the video that a lot of experts disagree on this, and that they're presenting their summary which you should take with a grain of salt!

Regarding Bangladesh...did you forget that they're looking at the connection between overpopulation and poverty? Beyond the obvious problem of crushing poverty being bad (which you get out of if you have "productive adults"), you're blaming them for focusing on the question you admit that they're trying to ask?! Yes, out of context it sounds kind of bad. This is why context is important!

In the Kardashev Scale video, they only state that it is reasonable to assume. Not that it's necessary. You don't argue that it isn't reasonable! You only that it isn't supported by lots of really high-quality evidence ("not in any way scientific") at which point...they wouldn't have said "it is reasonable to assume", but simply stated it as a fact. Sure, maybe they could have used very slightly weaker language, but this is hardly the type of criticism that should cause one to write an article doubting their objectivity.

And when you dismiss the "no system is doing an impressive job" comment on climate change, you assume (but they don't say) that they are claiming that all these ideas have been tested. It doesn't sound remotely like that to me. It sounds like "here are exactly opposite ideas, and we don't know for sure if either are true if you go to that extent, but everything that we have tried doesn't seem to be working". Completely fair.

And then somehow you say that they're advocating for traditional neoliberal solutions when they spend the last part of the video explaining why neoliberal solutions can't work (because deregulation and consumption is the source of the problem in the first place!). Indeed, they set off their solutions with (1) a very clear statement that it's opinion, (2) a non-neoliberal reinvisioning of how the global economy works, and (3) extensive public pressure on government officials to at least try to address the big problems...not because that's the neoliberal way but because all the incentives are to continue with business as usual unless there is widespread demand for something else.

I was prepared to be impressed my your points, but after listening to the videos, I actually don't see that any of your charges have merit. You perhaps want different things stressed--but if so, make your own videos!

Anyway, from what I've seen, Kurzgesagt presents a remarkably neutral, well-researched view, clearly identifying the level of confidence one should have in various claims by adjusting its language appropriately (speaking of fact vs. reasonable or plausible assumptions vs. opinion), and being willing to think outside any particular ideological box without losing sight of pragmatism and being bounded by observation.

(And, note: there is no reason from their videos to assume that "fact" means "could not possibly be wrong", as we have been wrong about such things before; only that our doubts should be low enough that it's not worthwhile to continue to apply skepticism except in those cases where we're very specifically testing the truth of that claim and/or relying on its truth to study something else.)

Really quite remarkable, and if there are flaws (as there almost surely are), they are mostly not the ones you have tried to level as charges. If they had been presenting their suppositions as facts, that would indeed have been problematic, but they go out of their way to do the exact opposite.

So I think your charges are essentially groundless. Furthermore, I am puzzled as to how you could have thought that there was a problem of this nature.