Previously On The Multiverse is a long and incongruous list that does the difficult (technically in-universe job) of a Previously On for the like 98 properties that happen to show up in The Book of the Snowstorm. Some of these factoids are important bits of information that you absolutely shouldn't be missing. Others, thanks to the well written actual stories later on doing exposition well, aren't even needed, and only come across as overwhelming. The few pages of this is a very overwhelming experience, really.

That being said, this whole thing does it's job well enough, and something had to be in this section.