Wikipedia seems stuck in an antiquated worldview where things like traditionally-published books with second- or third-hand reports of what happened, and which are frequently incomplete or wholly inaccurate, are nonetheless considered more authoritative than primary sources you can find with a ten-second Google search.So much this. Wikipedia's processes and policies are - in ways - an outdated and archaic relic of a bygone time. OTOH, I don't have a definitive answer ready "off the cuff" on what the standard should be. But I think everybody involved needs to acknowledge that the current setup is wrong, and needs serious thought and revision.
And the really insidious thing about this, is the fundamental asymmetry of effort between creation and deletion. Creating a Wikipedia article can take hours, days, or longer, of effort. Tagging an article as AfD takes a few seconds. The actual deletion (once whatever discussion happens) probably takes even less time.
It's amazing that anybody creates Wikpedia articles at all, TBH. I mean, you can spend hours on top of hours working on something and have it all mooted in a few seconds.