Technically, they haven't been maintained for a while now, but they haven't really been broken until 8.0. 8.0 overhauls the map code that finally puts nail in coffin for PVP mods.
Why are these mods being dropped when I work on DBM full time? I'm still only one person, and blizzard is pushing more and more content. Dungeons that stay relevant for entire expansion and continue to get new dungeons. Extra challenges like mage tower. In BfA we're getting scenarios back in form of isle expeditions (and DBM had good scenario support in mists and intends to do same for BfA). Not to mention rapid raid content. I even try to keep brawlers guild mods updated.
All this PvE content keeps me too busy to handle side projects like I used to. I haven't done a battleground in years. Literally not since mist of pandaria to be honest. The PVP mods are already out of date and missing some of newer BG stuff.
I had hoped by now I could have reached higher goals on patreon and done what I always wanted to do, bring on more help to outsource stuff like PVP mods to another person to work on. Unfortunately, do to fiasco in December with patreon scaring people off with fee changes (that ended up not going through) and continued decline of support in 2018, I'm not even making enough to support myself and mother, let alone afford additional help. I'm also not trying to be like "give me more money or I cut content". I'd continue working on everything if I could. It's simple logistics that it's too much for one person to do.
Just know that I continue to focus all time and effort on best PvE mods that I can.