Fine dust is sharp, not too bothered by gravity (meaning that it will rise as readily as it will fall), easily electrostatically charged, hygroscopic, will stick to anything and WILL get in everywhere. One day I noticed that my Vmax's matte grey paintwork seemed to have acquired some shinier edges. Those turned out to be the exact same edges its bike cover would bear on during storage and when adjusting (fitting and removing) the cover. I looked at my other rides and noticed that similar chromed 'cover support points' seemed to feature more fine 'anomalies' than seemed reasonable. That was about six years ago. I have not laid a cover on any of my rides since - these ranged from light fabrics (KTMs and Ducatis) to a heavy 'quilt' (Indian). I have repainted the Vmax.
Also, every time you wash a cover, it will be slightly less free-breathing as the fabric starts fraying and deteriorating ever so slightly - leading to another frequently reported issue; microclimate corrosion. And it is impossible to remove dust embedded in the fabric totally.
If 6 bar (90 psi) dry compressed air will not lift dust from any location on the bike, it clearly is time to wash, polish and wax it again - maybe twice a year at most.
It should be possible to pressurize a climate-controlled building like yours; very effective in keeping dust out and completely negating any reason to cover all the stunning rides there. One hell of a place that - man cavern rather than man cave (-: Top Job!