Fresh Air Systems sound great until wildfire smoke hits, then what?

During wildfire season on the West Coast, we get weeks where the sky turns hazy orange and the outdoor AQI spikes above 150.

Last year, keeping the windows sealed for 5 straight days made my apartment feel painfully stuffy. But obviously, opening a window would just fill the living room with wood smoke and ash.

This got me thinking about the logic behind Fresh Air Intake Systems. I was looking at pre-launch concepts like cozeware freshflow, which market themselves as windows Fresh Purification Systems.

In theory, if an intake unit has a thick enough MERV or HEPA filter, it can catch fine PM2.5 smoke particles while still letting fresh air in. But when AQI gets severely bad, does any outdoor intake risk clogging filters fast or dragging in odors?

Should these systems automatically switch to indoor recirculating mode, or is heavy-duty intake filtration enough?

How do you handle room ventilation when outdoor air quality goes downhill? Shut off all outside air completely, or rely on air filters?