I remember when a company would go through an acquisition and it was destined to then lose value on the stock market until they streamline their business again.

That's exactly what's happening here except it's a CEO change instead of an acquisition, and people are puffing this up for no reason. Twitter stocks have lost some value since the news (changes in CEO always do that on most cases), and then will go up again once they streamline their business in the mid-to-long-run. That's all there is to it.
By the way trading got suspended then, but now it's back on... as expected.