Most of us are comfortable with our knowledge on how to sail and have over the years learned about seamanship, both elements which have changed little over the years. For new people coming into the game, there are thousands of good books to read and learn these skills from.
Living aboard is not too different from living ashore and the challenges that face us in this respect are small, testimony to this the number of almost frivolous posts in that area over the years.
I believe that is why these parts of the board are not experiencing heavy traffic.
Maintenance and technology on the other hand are exploding and coupled to that the fact that with each passing year, not only are new boats becoming more complex but our expectation of what we want in our boats is expanding exponentially. Resultantly, a much greater portion of an old-boat owner's time is spent on trying to bring the new technology into their older boats. Whilst all of us have some knowledge in certain areas of this growing technology, it is a rare boat owner who knows it all (although there are some who think they do

).
In addition to this, seamanship, sailing skills and live-aboard details are inexpensive to learn and apply. Technology not so much. Mistakes and poor judgement can be really expensive so we don't jump into to it as easily.
Also, the rapidly growing cost of getting "specialists" in to do work on our boats is pushing more boat owners into doing stuff that they may never have contemplated before. I know a number of boat owners who always got a contractor to fix things and who now try to find ways to DIY. Boards like this are a good place to get the required guidance and information.
That is why, IMHO, the maintenance boards experience the heavy traffic. To be honest, I would have been surprised if it were any different.