They never did simply because there's way too many labors to release and collectors just run out of steam because asian audiences aren't as dedicated as western and there's so many stuffs to buy in Asia compared to your typical Sideshow + Hasbro.
There's a reason why there's so few Akira merchandise out there. Trading figures aside, there's hardly any supporting character merchandise other than Clown & Akira from McFarlane. I remember we only have the trading figure for Colonel and that is about it. Very few people would buy those supporting cast you mentioned simply because it's a cartoon. if it were a live action with notable actors as supporting cast it'd be something like Marvel movie lineup or star wars.
For GITS, Batau & Tachikoma are considered the more prominent supporting cast. sure section 9 cast are good but i don't think many people will buy their merchandise.
Even Appleseed only had mainly Deunan & Bariores figures, and 1 HT 1/6 Tereus. They had trading figures for another 2 subcharacters and the landmate.
Sure these shows are better than DBZ but you will see DBZ getting all sorts of characters released and you won't see half the cast from other shows getting a toy treatment.
HT didn't even bother with Alpha Deunan because Alpha Bariores was selling bad.
