Looks like a few others among this search for issued labelled as Bug with words xlsx and export experience at least something related. When it happens does Logs found in in the top-right menu (if it’s also there on the MacOS version) reveal anything?
Nothing revealed in the logs, unfortunately.
To add some information: it seems to be linked to query complexity as it only happens on queries with some LEFT or INNER JOIN. And when I limit the query results, I sometimes can export this limited result (and then have to aggregate data elsewhere).