Yet Another Package Manager :) Seriously - you're right, but people use curl | bash because it's super simple/fast and usually just works. Package managers can be an intimidating mess; even the choices we have in package managers confound things these days - did I install that with apt? snap? npm? pip? aw, crap that program I just installed with pip isn't working because I'd already installed a version with apt and some of it's configuration isn't compatible!!!
It's a mess. I really like snaps, but I hesitate for this reason - safer to default to apt on my ubuntu machine.
[edit] by safer I meant 'less likely for me to get confused and so screw up something', not meant as a security comment.
What you're describing there is a package manager. What we don't need is a tool for running any random script from the wider internet.