You've been told right GW, just putting birds in a separate room doesn't really do much good in homes with central air systems, then there's the cross contamination that you spread when you go from one cage to another, without changing clothes and/or showering, changing shoes and/or wearing bio booties around the house & changing when you change rooms.....
Based on what my vet has said, I'm of the opinion that the largest percentage of companion birds don't see a vet until they are sick or injured.....a couple of years ago I had one of my birds in for an initial well bird checkup & my vet mentioned that of the 30 or so birds he'd seen in the previous two months, only 4 were regular patients...the rest were either sick or injured.....he also mentioned that it was extremely rare that he saw 'keets or 'tiels, figuring that their inexpensive cost weighed on the owner's decision to buy new rather than on their bird's health & welfare.....sad situation.....
Knowing that this is of little or no good, I still advocate quarantine to new companion humans on the premise that quarantining is part of sanitation which is part of good bird husbandry & promotes better bird care.....IMHO.....