Theoretically yes, it is all turing complete at the nd. Practically no, it is the matter of established conventions. For example, most interactive installers I

Theoretically yes, it is all turing complete at the nd. Practically no, it is the matter of established conventions. For example, most interactive installers I have seen prompt for install location, and write minimal amount of files outside of it. The chance that they break your system is pretty low. At the same time, many |bash scrips like to install system-wide packages, or use pip as root, or other potentially breaking things. And they do not ask you before installing this, and often auto-confirm, too.