Quick summary
I would assume that Image blocks are supposed to be left aligned (not floated left however) when you don't set specific alignment. Testing multiple Varia and Blockbase themes they are centered by default. There is no way to set them to regular left alignment without the "Align Left" setting, which results in text wrapping.
Steps to reproduce
- Activate Maywood
- Add an Image block, don't set a specific alignment
What you expected to happen
Published page should look like the editor with the image to the left without text wrapping.

The caption probably shouldn't be centered but that's not the point of this issue.
What actually happened
It's center aligned.

The issue with setting it to Align Left is that the text wraps:

On Maywood this CSS causes the issue:

Context
Building a DIFM-L site.
pdh1Xd-78-p2
Operating System
macOS
Browser
Mozilla Firefox
Simple, Atomic or both?
Simple, Atomic
Theme-specific issue?
Every Varia and Blockbase theme I tested. Maywood is the example above.
Other notes
No response
Reproducibility
Consistent
Severity
Some (< 50%)
Available workarounds?
Yes, easy to implement
Workaround details
You could set the image to Align Left and add a Spacer block right under the image to break the float (so the text doesn't wrap the image).