A quick look through that list makes me think that 1) most of them are quite recent and not "written in the past 300 years" and 2) I read a lot and have not read or even heard of many of them. I also don't always agree with the categories the books are put into, like Lord of the Rings in Adventure rather than in Other Worlds.
I find lists like this interesting but also find most very silly. Here it's silly to have "our world" (the world of the six participants) defined by 100 works of mostly recent and often obscure English literature. That very narrow idea extended might be cause for much of the trouble our world is having. It's obvious they haven't read much really good stuff
I know it's a play and not in English technically, but any 100 list that doesn't include the Oresteia of Aeschylus, isn't worth reading. The Oresteia is the first in a continuing discussion of vengeance dished out personally vs jury trial by one's peers.
About 60% or so I've never heard of and some of the rest I've probably seen the film. There are categories that don't appeal to me and yet there sometimes are books within that category that I know and do.
It seems more like a list of personal favorites rather than a compendium of must-reads based on literary merit.
Of course I haven't read all those books, but because I buy books both for myself & for my mother, I wind up reading lots of reviews, so at least know a little about many books on the list that I have not (nor shall) read. I would swear, looking at the ages of the deciders, that the list is made up of stuff that was on their school reading lists, or stuff they know that we're supposed to read (probably from the old guy's school reading list), or a few things that are new enough to seem radical. (gratuitous capsule review from me: Homegoing is violence porn.)