The immediate problem is that an "automatic" contract circumvents the regular legal system and thus is going to be ... not-legal. The larger problem is that this is how things should be.
That the regular system isn't automatic but rather includes considerations of intentions and individuals involves is not a bug but a feature, an extremely important feature (the non-enforceability of unconscionable contracts is pretty important today [1]). Unbreakable contracts open the door for unlimited abuses (how does an automatic contract system prevent contracts for illegal activity? Given legality is going to continue to depend on intentions, etc).
The Etherium Fork illustrated all this and essentially discredited the approach.
Also, it can take a while for successful tech to be successful. But there's also the tech that people spend years trying to get going without success.