Technology, legislation and regulation have made huge improvements in air quality. The easiest and dirtiest problems have solutions, that have for the most part been implemented. Wood burning I believe is in decline. Right now oil is cheap. Electricity prices are declining when adjust for
inflation. I don’t see this trend continuing. I’m speaking for the US as a whole. There will always be a market for stoves and firewood. Regulations aren’t responsible for reducing wood consumption, economics are.
Steel prices are way up.( I don’t mind paying more but there better be an up side in the long run. That requires long term policy that is lacking) how many homes get renovated and the wood burner get removed?
A retrofit device is a good idea but unless it’s foolproof and nearly free it won’t gain traction. Can you imagine being required to bring your old car up to current emission specs?
An electrically heat CAT that sits above the stove with some style of fly ash separator seems like a plausible retrofit.