I already spoke with etabeta about the merging of the sysinfo.dat in the history.dat some years ago (2013 -- date of the last sysinfo update). The answer was positive except for the right to use the descriptions from old-computers.com present in the sysinfo. We have to write new descriptions for some computer entries (many are already done).
The History.dat goal since 2013 is to give historical information for every (MAME) games, (MESS) machines and softwares.