The following was a comment, made via attendees listening to the talk, regarding the study watchtower:
Changes to the STUDY EDITION to the WT, to simplify the style of the
standard edition. Allows for a larger font style. The GB decided, as of
January 1, 2019, they are combining their editions (so no more printed
simplified and standard editions).
Combining the Study WT and the CLAM Workbook would be an interesting idea - but it would appear to leave very little room for any 'important' non-study articles on topics the WT want the rank and file to know.
It would also be based on the assumption that people either use their tablets for both, or neither, and that they fall into two discinct groups with little overlap - ie rather than lots using the hard copy Workbook, but then most use WT on tablet.
Both the Study WT and CLAM Workbook are effectively internal publications and, in contrast to the old Kingdom Ministry', the WT is much, much freer on basically anybody attending the KH getting a copy of the Workbook.