The views expressed here are my own, not those of my employers.
I have been drawn to animal welfare interventions due to cost-effectiveness analyses consistently suggesting they are much more cost-effective than ones in global health and development. I think the 1st analysis I found along these lines was that from Stephen Clare and Aidan Goth, whose probabilistic model suggests The Humane League (THL) is 926 (= 25/0.027) times as cost-effective as the Against Malaria Foundation (AMF).
[note: my donation is currently paused for financial reasons, but reflects what is written below]
Put simply, if living with a huge amount of suffering animals is maybe wrong, then living with a raising amount of suffering animals is certainly morally careless.
It's due to general trends -humans globally seem to do better and better at helping one another, with fewer and fewer children deaths overall, people seemingly concerned by the suffering of other human beings, GDP rising, etc. I expect the ball to keep rolling.
Animals, on the opposite, suffer in greater and greater amount, and we don't seem to have found a real solution to revert this trend. Animal rights advocacy might end up being a "phase" in retrospect, and this is a worrying prospect. My hope is that my donations help build up momentum to eventually reach a tipping point.
Thanks for sharing, Camille! Relatedly, people may like James Özden's post The default trajectory for animal welfare means vastly more suffering. For somewhat opposite evidence, there is my post Farmed animals may have positive lives now or in a few decades?, and Robert Yaman's How to Be a Techno-Optimist for Animals.