> it makes me suspicious of the way the rest of the project is being made
This is why we can't have nice things. Because the developer rather focus their time on developing the project instead of the arcane packaging of the various repositories, the entire project deserves to be dismissed?
Piping curl to bash is basically the same as if you download the tarball/clone the repository and running `make`, but no one bitch about that. They rather cargo-bitch about "piping curl to bash is obviously always bad and your entire project is bad if you even include curl | bash as one method of installing".
Long gone are the days where projects are judged by the quality of the project itself, and today we want to get outraged as soon as possible, at every little detail.