Where is the analytics data supposed to go if you aren’t hosting a service to store it? Are you expecting the author of this free and open source analytics platform to also provide free hosting and storage?

all public bodies must disclose the source code of software developed by or for them, unless precluded by third-party rights or security concerns

So this effectively changes nothing.

Installing by piping from curl is pretty common and not a red flag in and of itself. Even Rust is installed this way. If you don’t trust the URL, you also shouldn’t trust any binary installers downloaded from that website.