The fact is that once smoke molecules permeate, they can't be removed. Some literally "kill" the odor molecule. No deodorant is powerful enough to permanently overcome the acrid, unique smell of smoke. A home vac does not have enough of the power needed to remove soot at the distance off of the surface that is needed to avoid smears. Even the brush at the end of a vacuum hose will create a smeared mess. But fogs and ozone are effective tools of smoke damage professionals. Professionals have to deoderize smoke - to take away the odor.
Ozone removes the molecule's innate ability to release a smell. The damage that you can see is from soot. Odor molecules, insulation and any permeable material will have penetrated fabric, following a fire, walls. Another technique is an ozone fog. It is very effective. And must be dealt with at the molecular level this is also a molecular problem. The problem with smoke odor is that it cannot simply be covered up.
The damage that you cannot see, but can smell, is smoke odor. And it will usually smear if brushed but the oily residue is holding the ash in place. Soot is also composed of ash. Which are needed because the hose must be kept a few inches off of the surface in order to prevent smearing professionals utilize very high velocity vacuums. It is tricky to tackle in a cleanup effort, and the care that must be taken to do it correctly is a major reason why people tend to hire a fire restoration firm to get it done professionally.
Drapes and carpet, when soot lands on fabric, because it appears ashy such as upholstery, the inclination would be to brush it off. Ozone treatments require the rooms to be sealed off. They have to attack the part of the smoke molecule that holds the odor. They must be disabled. The microscopic particles travels with smoke and are deposited on everything.