Maybe because there is simply no such thing as one-size-fits-all report.
The Dataform module is better equipped than the Database for this purpose although some of relevant functions have not been given attention lately and are likely broken.
One currently broken option is the export to portfolio which allows for exporting entries to html file. I don't think that I will be able to fix that in the near future, unless someone commissions the work. But, it may be possible to simply add an option to send dataform view content directly into an html file. I'll look into that and if not too time consuming I'll add it to one of the upcoming releases.
A working option which got some attention and should work reasonably well is the pdf view. It's a view type which allows the user to export the view content into a pdf file. It is currently not included in the standard release of the Dataform but can be downloaded from git at https://github.com/itamart/moodle-dataformview_pdf.