I would expect that the vast majority of concrete used in construction isn't poured into "arbitrary shapes," but flat walls. Even if only 50% of concrete is pored as flat walls, that would still be a huge market for this.
Re: acoustic isolation - having recently dealt w acoustics/concrete (laying a floor in a concrete apartment), I found out there’s not necessarily “concrete in general” so acoustic (and other) properties can vary from concrete to concrete.
- It can't be poured into arbitrary shapes.
- Much lower acoustic isolation