Presumably, she is arguing that hyperbolic proclamations are a valid way to get people to listen and engage in political discourse.
Of course, I presume that by "serious people" you are referring to scientists, but it definitely creates a mixed message from politicians- you know, the ones setting government policy.
At what point is it not hyperbole, but actual serious discussion? Should we treat everything as hyperbolic? All this does is confuse the problem (making it more or less drastic than it actually is).
In my lifetime, "serious people" have often made predictions about drastic things and were completely wrong- and they had models to support them! This is true about many things beyond climate change as well. Why should this be any different? Why should I believe that I should act, or believe that there is still time to do so? Is this a new hockey stick graph?
If you don't invest a lot of time sorting through all the BS, most people I think end up flipping a coin, picking a side and just going with it.