Too low a margin and too few customers to make it worth it for me to try and jump into those niches. Honestly, many of the benefits of using Erlang for those systems would have been similar to any other more service-oriented or decomposition of monoliths. They had complex systems doing too much, but that would have benefited from the really good binary processing portion of Erlang and it's relatively easy horizontal scaling story. But when the number of customer (organizations) can be counted on one hand, and the number of users is less than 1000, and there's already competition you know it's going to be hard to break in. They'd already hit rock bottom pricing on their contracts.