The following reasons could be taken into consideration if the images have disappeared from the website:

If you notice that the images have disappeared, the first thing to check should be that everything is up to date: WordPress, plugins, and the active theme.

There are cases in which the plugins were updated but not the platform or theme, and vice versa. In some cases, an old plugin version, along with an up-to-date theme/platform, can cause faulty functionality.

After you ensure that, check the website from Chrome -> Incognito mode or Safari -> Private Window to ensure you are not viewing a cached version of your website.

One of the most encountered situations is when a plugin conflicts, blocking the images from being visible on the front end (what visitors see).

To check this, deactivate all the plugins with no exceptions and navigate to the website from a Private Window or Incognito mode in Chrome.

If the images are present, it means a plugin is conflicting, and you can activate each one, refreshing the website after each activation to see which one is the culprit. 

You can find an alternative plugin at www.wordpress.org/plugins

There are situations in which the images are missing due to the hosting services and user permissions or space on the server where the website is hosted.

In this situation, getting in touch with the hosting company and telling them to check should fix the issue.

Another situation is when the images were manually deleted from the server to free up disk space.

Example:

The image was uploaded to a page using The Divi Builder or the Default WordPress Editor.

When that image is added, it's uploaded via the Media Library.

At that moment, WordPress automatically creates a folder on your server that stores all the images uploaded through the Media Library.

Example: /wp-content/uploads/2023/07/myimage.jpg

In this case, the image file named myimage.jpg was uploaded in July 2023.

If, in the meantime, that image is deleted from the server for any reason (manually or by an optimization plugin), the path remains active in the front end when you access the page. Still, with the image missing from the server, there will be nothing to show on the front end.

You can check that by inspecting the page where the image is missing and checking the path: 

The 404 server error indicates a Page/File not found. Reuploading the missing images and assigning them again in the page layout will fix the problem.