This is one donor, not "the person behind". The family made a lot of money on oil and has since entirely divested. The "heiress" in question is on the record saying she believes climate change threatens all of civilization and so she wants to put her fortune -- especially given that a lot of it came from oil -- to use stopping fossil fuels.
It's basically EXACTLY what a sane person with a functional moral compass should do in that position, but it's used as attack and slander regardless. Threads like this you ALWAYS see the right-wing talking points parroted faithfully by people who are either too gullible to do basic fact-checking or else are flatly disingenuous and manipulative.