I think the 8GB model probably exists as much to hit a price point as anything else, but I absolutely noticed that memory usage on the Apple Silicon Mac I'm typing this one has been drastically better than it was on the Intel Mac it replaced.

Enough to claim 2:1? That seems fishy. But! I bought this machine with half the RAM of its Intel predecessor, and I haven't noticed a problem despite my ongoing tab-and-app packrat tendencies.