why are native english-speakers "the world’s worst communicators"?

It seems that so-called 'native speakers' of English are very, very bad at communicating:

Decades of research show that when a native English speaker enters a conversation among nonnative speakers, understanding goes down. Global communication specialist Heather Hansen tells us that's because the native speaker doesn't know how to do what non-native speakers do naturally: speak in ways that are accessible to everyone, using simple words and phrases.

Why Nonnative English Speakers Actually Speak The Best English : Goats and Soda : NPR

And from the BBC:

“A lot of native speakers are happy that English has become the world’s global language. They feel they don’t have to spend time learning another language,” says Chia Suan Chong, a UK-based communications skills and intercultural trainer.

“But… often you have a boardroom full of people from different countries communicating in English and all understanding each other and then suddenly the American or Brit walks into the room and nobody can understand them.”

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“It's the native English speakers that are having difficulty understanding and making themselves understood.” Non-native speakers generally use more limited vocabulary and simpler expressions, without flowery language or slang. Because of that, they understand one another at face value.

Native English speakers are the world’s worst communicators - BBC Worklife

Here's a classroom activity based on that piece - an activity for 'non-native' speakers looking at 'native' speakers!

Native English speakers are the world’s worst communicators — English Language Inbox

Because 'non-native' speakers have a real problem understanding 'natives':

With a couple of videos:

Why Is It So Difficult to Understand Native Speakers? - Ouino Languages

Why You Can't Understand Native English Speakers | Go Natural English

Why it is so hard to understand native English speakers

Finally, here are some tips for the native speaker on how to communicate better:

Native English speakers are the world’s worst communicators – South Coast Herald

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