Hey just to update anyone else who was curious about this, yep automation tooklit totally isn't included in the base SD2019+ license. It used to be included up until 2017 when they seperated it because it "significantly evolved" since that version. Mostly it seems this was because they knew a lot of AAA devs had become embedded with the tool and they could eat the increased cost.
Unfortunately there is no reasonably priced purchasing tier option for Indie devs since there is only a $5000/yr option, and my inquiry to ask about other options yielded no response. I was shocked to find this out, as our company currently uses the older batchtools (which near as I can tell is quite similar to the new automation toolkit), so as we upgraded to SD2019 we were caught in a pickle.
If I sound a bit sour, it's because this was a very quiet change and they did not make any announcements about the change, and our pipeline was a bit broadsided by this. I can fully appreciate their right to make money and change pricing models as they see fit, this is a business after all. I just don't appreciate the opaque nature of this change, one that would affect any developer thinking to upgrade their SD licenses.