OTP fuses can be made in any technology, either poly or aluminum. Similarly any such fuse can be characterized. But then you start to care about reliability, regrowth / marginal blow, and the circuitry to sense fuse state and protect anything else attached, from the blow- event (flyback voltage on opening, etc.). This may be where the foundry has reached initial success and then stopped; I have worked fuse "bolt-on" developments where everything was going fine, not a single failure in programming or small-sample tests. But a new product development director did not want to hear about the $40K to rent lifetest oven space for the needed 1Khr qual, and killed the project - screwing a family of products as a result. All good for him, though - got made a VP (for what, I couldn't see) and then shortly he was on his way to a new company leaving only a mess. The fuses never did get qualified.