99.9% of the people have Direct Lines at their work phone. Most companies don't have receptionists and if they do their primary job is not answering the telephone.

With this reality, what does work phone accomplish for providers?

Just curious to find out.

They can google the phone number or look it up and see if it is actually a phone number to the place you work.

when the phone was answered.  This way they know you work there and are not LE.