notformer,
Funny observation on the preaching during Covid. I guess the safety of members getting ill trumped possible in-person contact in the ministry.
In answer to your "Does D2D result in conversions any more? Even twenty years ago it was not looking like a very effective use of time," that's a fascinating question. Traditionally one factor has been the socio-economic area where the preaching takes place. A lower-class area has had a much better rate of "Bible studies"/conversions than a middle- or upper-class neighborhood. But even in those poorer areas, conversions has slowed greatly or even died out since the GB dictators decided to quash the emphasis on getting into conversations, and just tell the "faithful" to direct people to the WTS website. Now it is slowly dawning the GBers that it's time to go back to imitating Jesus and the first Christians in personally speaking to people, acting in a human-to-human manner.
Again, DUUUHHHHH.