I appreciate the Zen Buddhist (with a mild leftist slant) take on reincarnation. Questioning the existence of reincarnation is asking the wrong question.
If it’s real, you have nothing to worry about—you’re living the best life you can given your material conditions. So it’ll work out.
If it isn’t real, you also have nothing to worry about—you’re feeding trees now.
The right question is what you can do better, right here and now. The only life that matters is this one.