I don't think it's possible for this sort of individual, opt-in action to be material to the climate problem; problems at this scale can only be solved by government action. If Stripe raises $30M/year from this program, it'd be like 10000x too little to be significant to our carbon problem. (Maybe it could have some minor R&D acceleration impact for the carbon removal techniques they're looking at).

The root cause of our climate problem is the fossil fuel industry having successfully manipulated the government and public to prevent real action on climate change, for decades. The Drilled podcast is a good resource for primary source material on how oil companies systematically manufactured climate change denial.

I would prefer that Stripe allocate the funds to groups working to counter the fossil fuel industry's misinformation strategy. $30M/year would be a significant budget for that sort of work.