For a while Wikipedia had such a complete list that we ourselves used to refer to it. Then some wikipedian decided to "improve" the list by deleting most of them. Since then it has always been a more or less random subset of YC funded cos.
I guess there should be a separate page listing all YC funded companies (if you can have pages listing all characters in tv series, why not companies funded by YC?).
Because the standard of 'notability' is bogus when applied to something of the supposed scope of wikipedia. It's impossible to apply it with any reasonable consistency, and it always boils down to a few biased opinions, which is why the topic of notability deletions is so sensitive.
