They're not as partial and biased as people like to believe.
When you read kurzgesagt's reasoned response, and you consider the motivations of the primary accuser, it's a lot less dramatic than you make it sound. Nobody's perfect; and sometimes organisations' messaging align without it being bought. They are not primarily funded by billionaires, they have editorial independence enforced by contract, and have a lot to lose if that's not the case. Of course, make up your own mind (as kurzgesagt would like you to do); but I'll still be watching their work. If in doubt, check with other sources afterwards! (Like you should anyway).