Many problems are very latency tolerant. Unless you have an algorithm which is truly latency intolerant, I argue you are best served not investing in low-latency interconnect because it costs so much.

When I ran Exacycle, we distributed protein folding, protein design, drug discovery, telescope design, and other problems globally. We never had an issue with latency, because these problems all partition really well. People who claim supercomputers are "necessary" for these problems typically construct problems that are well-matched to supercomputers (for example, running molecular dynamics on huge proteins) but they tend not to have very high scientific value.

In my experience, partitioning to minimize communication has always increased my total scientific throughput, while programming to supercomputers has always reduced it.