Reasonable advice, but I’d note that I pay for premium and patreon specifically because I can only afford patreon for a few creators. I’d rather pay everyone I watch. While YouTube isn’t perfect, I like the service enough that I don’t mind paying for it.
Your time and energy is far more valuable than your money.
I would recommend using that money as an emergency fund, and getting involved with an activist organization working to stop climate change. There are a wide range of them, with tactics ranging from legislative pressure to property destruction and civil disobedience. Believe it or not, there are lots of small local problems that a small group can meaningfully impact, and will add up.
While there are systemic problems that cannot be solved by an individual, they can be solved by collective organization. You have to be part of that collective if you want to stop climate change.