This is cute, and definitely a good educational resource about mature foss HCI applications, but this will not give the degree of quality that many have come to expect from assistants as simple as even Amazon's Alexa. Sirius is much closer to what you want.
After a casual read: yes, I believe so, in that it does not require 3rd party API's. You do still need to run it on a server that your client device can connect to. If your goal is an assistant that does not report back to Apple/Google/MSFT/Amazon, then Sirius looks like another good option.
Was interested in this but from my reading of the docs it looks like it just queries a local instance of Wikipedia? So I couldn't ask "What's the weather today" or "Do I have an appointment on Saturday" or "Who won last night's Redskins game?". Which means it's a neat toy but nothing I'd ever use.
http://sirius.clarity-lab.org/sirius-suite/