My suspicion was that it's getting confused by the line above the intro, but I pasted the article's source code into Wikipedia:Sandbox and gopherpedia read the intro just fine. Strange!
That was my thinking too but I can't find a revision without it on the first page of results going back to 2019. Why does it look like a recent edit to you?
The markup behind that article isn't terribly complicated, but the parser isn't perfect either. For example: https://gopherpedia.com/gopherpedia.com/Gustave_Dore has some glitches in the lead sentence.
My suspicion was that it's getting confused by the line above the intro, but I pasted the article's source code into Wikipedia:Sandbox and gopherpedia read the intro just fine. Strange!