I'll add my thoughts to this...as stated in another thread, I don't have any inside information. Just years of experience with their gear and watching their marketing.
IMO, Their current line of AG series amps are pretty light (17 and 18 lbs). The recent trend of ultralight/micro amps has produced models that are convenient for people with health issues and light travelling needs, but they aren't selling off the shelves and have a very niche market. They sacrifice tone and cool looks (c'mon, who doesn't like staring at a massive rig?) for weight. Ok, some may even sound good but how good compared to other stuff? From my own experience, the few times I did need something smaller than an AG500 and a 1x12, I just used a DI.
It just seems a bit pointless to devote resources to making something aimed at an already flooded market. Stick with what works for you, ya know? And having said all that, who knows? Either way, I think Aguilar has cemented their place in the low-end world and can afford to wait and see where this trend is going. I don't think it would take a whole lot of effort on their part to mate a Tonehammer to a 500 watt micro power section and sell it. Hell...we'd all probably buy one! LOL