This seems to suggest you would be right:

if(NOT SKIP_TSK AND NOT WINDOWS)
    list(APPEND TABLE_CATEGORIES "sleuthkit")
  endif()

This seems to be code from osquery pre 4.x though, while now the table is indeed enabled on Windows. This has been copied originally by the Buck build system from the experimental version. I guess the intention was to make it work on Windows too or something similar. In any case, I'm not familiar with the table, so definitely we need to look into it.