In my 70 plus years experience I have never seen a vacuum in a production machine shop. They all had compressed air at the machines. For the answer you really have to understand the world of Machinist, Toolmakers,etc. They are very intelligent people always striving to obtain more knowledge and they are meticulous in caring for their tools and machines. No matter who or what company they work for they consider the machinery and tools their personal property and treat it as such.
They will use whatever does the job best without damage. Most importantly they will know how to use air without hurting any thing or anybody. If they are not sure they will not do it.
The right answer is Do what you know how to. If its suck suck, if it's blow blow.
In that 70 plus years, I have never seen a machine damaged by cleaning and oiling it. USE YOUR COMMON SENSE.