Zulip got a foundation at the same time, literally the best that could have happen to the FOSS parts of it, basically a dream come true for the people relying on it to continue being FOSS.

Let's see in a few years how the development of Zulip has progressed by then. It is not a foundation like Zig, where the main guy is actively working on it. It is the best that could have happened, except of course the top people staying on.