Don't get me wrong, I use async/await almost exclusively these days - but I've run into these problems in large real world applications, and they can be hard to fix.

This isn't FUD if the main implementation is "broken".

With regards to errors being swallowed, I'm not talking about unhandled rejections, I'm talking about code that mishandles rejections and may swallow one intentionally, or code that doesn't pass along errors properly.