And for a good reason: your grandfather's recollection of WWII, for example, has no place in an encyclopedia, but it's surely more interesting and possibly instructive than reading about it from a history book. I'm saddened we're losing this.
It doesn't have a place in an encyclopedia, for sure, but I posit that Wikipedia is not an encyclopedia. It was supposed to be, and ostensibly started as one, but the amount of content that gets placed into it (and then removed by the mods...) shows that a sizable amount of Wikipedia users use it as a "knowledge repository" instead, which I think is subtly different.
I mean, I wish we could collate the entire set of human knowledge into one place, however Wikipedia says that it doesn't want to be that place. The thing is, when you've already got 100,000 word treatises on Sailor Moon due to some Admin/Mod having that as his/her pet topic, it smacks of elitism, favoritism and hypocrisy.
A problem is that it's not necessarily more accurate. What Wikipedia wants to be, and which I think is valuable (though it's not the only valuable thing) is a summary of the best published information on any given subject, with references to that published information backing it up. So if I read a Wikipedia article on, say, Treblinka, I expect to get a summary of what historians think happened there, with references to where they say so. Where they don't agree or are unsure, I'd like a neutral explanation of any significant areas of uncertainty or historiographical dispute (with citations to the relevant sides), etc. I really don't expect to get a personal recollection by one Wikipedia editor's grandfather of what happened there... especially if that recollection contains information that isn't consistent with what's written in the mainstream histories.
It's possible that the recollection may sometimes actually be better than the mainstream histories, though in such a well-studied subject as WW2 concentration camps I think the odds are fairly low. But in either case I think that's a job for someone other than Wikipedia: Wikipedia's job is to summarize the current historical understanding. Revising the current historical understanding in light of new information or arguments is a different and very large job in itself.
