+1 to these modules removal.

One concern I have is when users follow internet examples and look out for these modules or examples.

What is the best way to show them the modern usage? 

- Should Python docs show some example snippet of the most common usage of aiosmtpd ?
- Echo server / client using asyncio.

A stdlib page dedicated to removal, and showing examples using these modules, especially aiostmpd as it is not a part of stdlib, might be a good idea.