I think your comment is pretty spot-on.

One thought about the WALL-E scene though. While I'm not at all advocating the satiation of everyone, I do wonder about its perceived inevitability. If that was the only outcome, wouldn't we see evidence of this with the extremely rich today? (I'm talking about the case where wealth was strictly inherited here, not the self-made fortunes from hard work.)

I don't have any examples in mind, but I do think it's worth asking the question. If we assume those who are satiated would not work on anything of value, that might very well contain a similar misunderstanding to what you've highlighted here. We just need more data to know what level "too much" really is, or if that's even a thing at all (I believe it is, but I certainly can't prove it).