Hi @christianmuellerdhv,
It still shows in the same way for me. I believe this is the default design with Twenty Twenty-Three — this would only show differently if you are using a child theme or something like that.
Full Size: https://d.pr/i/nWtihy
If you want, you can try to see how it works from this code that I generated here:
<!-- wp:image {"id":171,"sizeSlug":"large","linkDestination":"none"} -->
<figure class="wp-block-image size-large"><img src="https://wptest-multisite.mystagingwebsite.com/base-site/wp-content/uploads/sites/8/2023/08/4919c4c9-9033-342f-909f-a75a11685610-1024x682.jpg" alt="" class="wp-image-171"/><figcaption class="wp-element-caption">This is my caption.</figcaption></figure>
<!-- /wp:image -->
<!-- wp:columns -->
<div class="wp-block-columns"><!-- wp:column -->
<div class="wp-block-column"><!-- wp:image {"id":171,"sizeSlug":"large","linkDestination":"none"} -->
<figure class="wp-block-image size-large"><img src="https://wptest-multisite.mystagingwebsite.com/base-site/wp-content/uploads/sites/8/2023/08/4919c4c9-9033-342f-909f-a75a11685610-1024x682.jpg" alt="" class="wp-image-171"/><figcaption class="wp-element-caption">This is my caption.</figcaption></figure>
<!-- /wp:image --></div>
<!-- /wp:column -->
<!-- wp:column -->
<div class="wp-block-column"><!-- wp:image {"id":170,"sizeSlug":"large","linkDestination":"none"} -->
<figure class="wp-block-image size-large"><img src="https://wptest-multisite.mystagingwebsite.com/base-site/wp-content/uploads/sites/8/2023/08/bedb708b-aff6-32e1-85a0-d32d3bf0636b-1024x682.jpg" alt="" class="wp-image-170"/></figure>
<!-- /wp:image --></div>
<!-- /wp:column --></div>
<!-- /wp:columns -->
If even that doesn’t work, can you try to reproduce the same issue with a brand-new installation (without other plugins/themes) and using Twenty Twenty-Three?