I am surprised that so few people discuss the centralized, presumably less-wasteful, less-cluttered alternative that is a furnace-adjacent air bypass + filter (

I am surprised that so few people discuss the centralized, presumably less-wasteful, less-cluttered alternative that is a furnace-adjacent air bypass + filter (particularly relevant for those of us with access to our own fans/furnaces). The idea, as I understand it, is that a furnace can be modified by an HVAC specialist to send a portion of the air through a low-flow bypass duct containing a HEPA filter (or some other high-MERV-rating filter). This highly filtered air is, of course, combined with the less-clean air that passes through the low-MERV (standard) furnace filter before being delivered to ducts/rooms. This enables filtering of air for the entire living space without the need for an air purifier (a large plastic box containing future e-waste) in each room where clean air is desired. One obvious shortcoming of such a system is that in-duct/in-room sources of particulates (including concentrated bursts of particles from things like cooking) might be harder to combat. I don't know whether such a system can reduce particulates to levels commonly reached with in-room purifiers. Thoughts/adecdata on such setups?