My anecdotal evidence is a bit different. For two years (2015-2017) I lived in one place where they did come around 2-3 times a year (surmised from tracts left in my door). I was always gone save once. That time was a lone, middle-aged sister. What struck me was the zero attempt to engage me in any meaningful conversation. She had a tablet, read no Bible passage, offered no literature, and just invited me to a meeting. Given that she was alone, I figured she was a pioneer who was getting her hours in. After that I moved and lived in another location for one year. It was a secure building, so they did not come by. However, the neighborhood was mainly accessible single-family homes and one time I had to park on the street about a block away. When I went to fetch my vehicle, I found a group of 5, 2 bros and 3 sisters, going D2D. We chatted a bit so I could find out about local downsizing. Sure enough their KH was going up for sale, and according to one sister, gullible enough to buy the party line, the money from the sale was for "KH building in foreign lands." Anyway, it's just my experience and I realize that is limited and the situation may be different elsewhere, but in two places where I've lived for the past 3 years, it's both carts and D2D.
If the carts were planned by the Muppets, err, I mean the GB (thank you, Orphan Crow!) for making it easier to pioneer, it's a remarkable case of them being proactive instead of reactive.