Kaj Sotala's post wasn't about how to talk to random strangers, but how to get to interesting conversations to some you're already talking to. It's a bit unfair to accuse people who are here to help with that issue of not being helpful on a related, but different one.

Perhaps, but your advice required the ability to successfully start conversations, since you were suggesting to talk to random people:

Who doesn't have easy opportunities to increase their number of conversations, other than a total shut-in? People are everywhere, and therefore, so are potential conversations. You might not have the most interesting conversation with the guy standing behind you in line at the bank,

It's true that practice is necessary, but not just any practice will suffice. And following the practice recommendations you gave would not be helpful unless the problem were mostly solved to begin with.