"it's too narrow to justify the investment into building specialized hardware for it"
FYI, if the only way to improve perf is to build custom hw, the cost and complexity of building custom hw will drop.
Erm... Not necessarily. The only way to travel quickly between 2 cities is a direct flight, but there isn't a direct flight between any 2 cities, because the cost of having such a flight didn't yet drop to the point where it's economical. So it will be with many types of custom hw.