I would not take this benchmark to draw general conclusions.
The spinning disk result is only 10x slower than RAM. But a spinning disk's throughput is 100-1000x less than current RAM, and for latency it's even worse.
Similarly, the other factors in the benchmark graph are way off their hardware factors.
This benchmark is measuring how one specific program (the Haskell Compiler compiling ShellCheck) scales with faster memory, and the answer is "not very well".
The overwhelming majority of access would still happen in the 2GB RAM the benchmark has. The disk is only hit to stash or load overflowing pages, not on every memory access. That's why it doesn't mirror the hardware difference between DRAM and disk.
The spinning disk result is only 10x slower than RAM. But a spinning disk's throughput is 100-1000x less than current RAM, and for latency it's even worse.
Similarly, the other factors in the benchmark graph are way off their hardware factors.
This benchmark is measuring how one specific program (the Haskell Compiler compiling ShellCheck) scales with faster memory, and the answer is "not very well".