On an individual interview, it's possible to quickly click "Summary" under AI actions to summarize the overall interview. The "Insights" section at the study level also has a "Summary" field, but it must be manually populated at this time.
It is possible to use Elle in the "Summary" field if you click into that field, run Elle, and prompt it to summarize the specific study you're in. You can then insert that into the field. This takes multiple clicks and knowing the right prompt to use.
There should be an optional way to run the "Summary" action across the study and populate it into that field as a starting point without using multiple clicks or crafting your own prompts.