I actually don’t expect the RAM requirement to go up by much. These learnings were based on artificial high load tests during early testing with an artificially low number of nodes. The more nodes there are, the more peak usage will be spread across nodes and the lower the RAM demand.
Additionally it’s worth to keep in mind that when running multiple nodes on 1 system, the traffic is spread across those nodes anyway, so apart from some RAM overhead for duplication of core processes, I would actually not expect a large RAM increase for running multiple nodes. And you may even be able to get away with running 4 nodes on 2GB.
That last part is speculation though and not yet based on actual tests or user feedback. I am however pretty confident in saying you will never need anywhere near 32GB, no matter how many nodes you run. You’ll run into other bottlenecks way before the RAM is an issue.