There are a few veins in this thread, so I'll address them separately.
I agree that the biggest challenge in this game is knowledge, and information. Whenever I pick up a new player, the first things I teach them are how/where to gather resources, how to craft basic weapons and ammo, where and what to hunt, how to level, and try to help them kill 10 cows for their tent. I don't like giving tents out, I don't often give out weapons/ammo/armor, but I like making them work for it. In my mind it fosters a sense of accomplishment, while teaching them the basics they need to survive in the game. The advanced stuff will come in time, if they stick around long enough to get there. Sometimes they do, often times they don't. One thing I've noticed when talking to some of those new players on Skype weeks later, is that they quit simply because they didn't find the game enjoyable. Not because it was too difficult, or PK's, or lack of content. Whatever new game was just released catches their attention more, or they have school, etc. Sure, people ragequit due to harshness, PK's, etc. But I have a feeling that the large majority of new players who stay a few days/weeks and leave, do so quietly, for no particular reason other than they move on.
New Player Day Care might be of some benefit to new players, but I don't think it'll actually raise the server numbers. There have been some good, and bad suggestions on this for a while now. Those threads are still there, if someone wants to find them. However, the Dev's have stated that it's not gonna happen, so I'll leave it at that. As far as my thought that it won't affect the sever population, refer to my previous paragraph. This game simply isn't for everyone, so people often tire of it. Giving people an easier start won't prevent that.
Lastly, the playerbase themselves. Yeah, this place is full of insufferable, know it all douchebags. So are a lot of places I've been in real life - that's how people are. I feel like the anonymity of the internet just amplifies that, and not just this game. Other games, forums, you name it... that's how people are. Nothing can be done to change this.
Also, when you really think about it... it's possible to have too many players, as well. Of course I want more people playing, I've enjoyed this game for a few years now. I hope others enjoy it as well. I would like new people to play with, and I would like a more populated wasteland. However that comes with a drawback. If the server numbers doubled, tripled, or quadrupled - so would the number of douchebags. It's naive to think that only the people playing now have filled the douchebag limit. If the playerbase grows, so will all the other good and bad things that comes with it.
A high server population, may actually make griefing, trolling, and PKing worse.
.02