This is getting a little ridiculous. I'd wager that a pretty small percentage of diesel owners actually delete, particularly since the newer DEF systems were adopted, and the health and environmental impact of those who do is a pretty small drop in the bucket compared to everything else we're exposed to in modern life. 90% of the time I see black smoke blowing out of a diesel pickup it's an older pre-emission truck. I guess it wouldn't surprise me if more of the newer trucks get deleted as they come out of warranty, but an awful lot of people such as myself live in areas that have mandatory emission testing, so it isn't even an option for a lot of people.
Getting upset at somebody who wants to delete his truck seems a little over the top, but maybe that's just me.