Much of that information has to do with creating a new hardware port from scratch. The i386 support just needs to be "demoted" to the Debian ports infrastructure once it's officially scheduled to get dropped from the main Debian repository (which could well happen starting either in Debian forky or duke), and this can probably be done with some special handling.

(Answering the "to what end?" question, a lot of 32bit-only hardware is still available and dirt cheap in the second-hand market (e.g. early "netbooks"), much of it quite well-built and enjoyable to use. While such hardware can no longer realistically browse the "modern" web, it can still find a lot of use for more lightweight tasks, including acting as a "thin client" for more powerful machines.)