it is because the website providing the image is overloaded and cannot create an image.
You just have to reload the image and eventually you will see one.

Exactly. The text of this post is simply :

![An external image showing your user-agent and the total "hit count"](https://trilinder.pythonanywhere.com/image.jpg)
I get the same result when I browse directly to the link.

So, if OP links a malcious website we have a problem … (?).

“AI Generated Images” ?