If the actual installation process can be made simple, you can have users copy/paste the whole installation script rather than pulling it down with curl.
Guix setup used to look like this but now they have a shell script for download. Even so, the instructions advise saving it and walk you through what to expect so you can have reasonable expectations while installing it.
Anyway, my point is that there are other ways to instruct people about the same kind of install process.
How do I install npm? The npm webpage tells me to go and install nvm. At that tells me to use curl | sh .
So using npm for a new user is still requiring a curl | sh, just in a different place.