> But nobody is forced to use curl?

I like curl, but this isn't true. When you're SSH-ing onto a box, you often don't have permissions to install your favorite CLI tool, and even if you do have said permissions it's inconvenient to have to install it each time you SSH onto the box (not a major inconvenience, mind you). Moreover, in many cases you need to run a script or some other software that depends directly on curl.

In general the "nobody is forced to use it" arguments rarely pan out (I remember this was a canned argument from C++ folks circa 2011: "C++ is the best language because it has every feature and if you don't like some features, you aren't forced to use them!").