This is not at all a new problem for Python. In fact, it's possibly more of a problem for Python than it is for C++, because Python's dynamic nature and exposure of many internal mechanisms makes it possible to do some pretty crazy stuff in the libraries.
For example, speaking of async - even 2.7 already has Twisted, and an ecosystem of libraries around it.
The only two ways I can see it being solved is either by making it more of a toy language (which is great if you're just writing short scripts, but it's not really what it's supposed to be about); or by having a very centralized "best practices" enforcement that basically forces libraries to conform through peer pressure, like Java - which has its own disadvantages aplenty.
For example, speaking of async - even 2.7 already has Twisted, and an ecosystem of libraries around it.
The only two ways I can see it being solved is either by making it more of a toy language (which is great if you're just writing short scripts, but it's not really what it's supposed to be about); or by having a very centralized "best practices" enforcement that basically forces libraries to conform through peer pressure, like Java - which has its own disadvantages aplenty.