Requiring nothing but a standard Python install is a big benefit for an application. I have certainly written code which uses suboptimal library modules, just because the suboptimal ones are standard. So improving PyPI, while a worthy goal, isn't the end of the story.
In fact, just getting Python installed can be enough of an issue to be a problem. For some recent work, I ended up proposing TCL (ack, spit) because of the existence of Tclkit - a one-file executable which included TCL and a load of libraries. And binaries for most common Unix flavours, and windows, are available for download. Zero-cost install with no need for a compiler is a major benefit in highly heterogeneous environments (where you can't rely on much beyond the base OS, and that varies, and change control policies vary enough to make being able to install and/or rely on a standard scripting language pretty much impossible). [Real life - who needs it :-(]