One big reason places like Wikipedia and Stack Exchange became so amazing is that they have developed a very tight culture of quality: although it's true that anyone can contribute, in reality every entry is relentlessly filtered, edited and reviewed by a core group of committed contributors.
In the early days of the WP it was possible to append some nonsense to an existing article, and even (gasp!) start a new article with content of very poor quality. Those edits could stay unchanged for a very long time, and so it was relatively common to stumble upon pages filled with illegible stuff or including made-up gibberish without sources or external links. I know that because almost two decades ago I contributed a little for the first time to a couple articles (like “Granada”), and the few sentences I added stuck for months or years (not that I trolled or wrote anything false).
On the other hand, my recent (little) experience trying to contribute to WP articles has been less sweet. In the last years I have fixed typos and grammatical errors without any problem. However, when it comes to starting a new page or adding more than a few words to existing ones, I find that rules and etiquette are so stringent now that they raise the bar way above the time I can spend on a WP page as a quick distraction from work or whatever I am doing at the time, and so my edits have been sometimes questioned or reverted.
Ditto about Stack Overflow and all the other sites of the SE family. I remember well the refreshing feeling when Atwood & Spolsky launched the thing: it was bold, easy, incredible quality and very helpful. It's still all those things… but for the “easy” part. Today it's so easy to misstep (asking or answering a question) that sometimes it can be intimidating. “Too short”, “too long”, “answered elsewhere”, “add fewer tags”, “should provide and example”, etc.
(As I said at the beginning: I know I shouldn't complain, because those high bars and the incredibly serious army of contributors is precisely what makes those sites high quality, useful, and mostly reliable.)
Anyway, I was reminded of all that last week when I read about ChatGPT.