Ever since the web browser was created, way back in 1993-1994, the paper trade directories have been doomed. They are only updated once a year, they are often out of date or incomplete. ISA has tried before to replace its venerable Directory of Instrumentation with online versions, but they have been basically klugy and not very user friendly.
Besides, the Directory of Instrumentation didn't reflect ISA's new name. So it needed to become the ISA Directory of Automation. But with ISA's recent headcount reductions, they didn't have the staff to do it in house.