Testing this out myself, I received the same output. From what I can gather, I think a table preview is populated in that box until the last step, but the weird thing is the table preview is semi hidden. I say semi hidden because in certain areas, values can appear if your cursor goes over it. In this particular instance, I do not believe this is the intended behavior, so I would suggest to create a support ticket. Please refer to this resource on how to create a support ticket (Case management - AWS Support).
Now for a workaround, I would suggest using the Chat agent feature, if you have these capabilities turned on in your environment. Recently they have added the feature where you can connect datasets directly to the chat agent and it works similarly to the topics. In some instances, I would say it works better than topics (depending on your data) and it also gives you the option to see an explanation for every question you ask the chat agent about your dataset.