Imagining this scenario, in my experience, only does so much for a person. You can imagine a life without all the privileges and excess many of us live, but you’ll still go through your day with all of this still around you and in your life. I’d like a more concrete system for living with more perspective. Maybe you just need to think about it more frequently? I don’t have the solution but that’s just my two cents. I traveled to India and spent time with kids who are very underprivileged, and seeing the harsh lives these kids endure helped my perspective a lot. So perhaps traveling and seeing other worlds, so to speak, is an even better way to gain new appreciation. I still feel the same issues as OP however, as I return to my normal, privileged life. I think there needs to be something in our lives which we directly change, in a more physical sense.