While I don't have a large sample size to prove this, incredibly high edit numbers on these sorts of non-news events tend to be just one person. These people are unpaid and can focus on whatever they want, and sometimes they just want to edit one page.

That said, accumulating /thousands/ of edits is definitely unusual. For example, my top-edited article is the South American dreadnought race, where I've made 800 edits over four years.[1]

For another example, last year's list had "Geospatial summary of the High Peaks/Summits of the Juneau Icefield" at #2.[2] It was just one person making over 7,000 edits.

[1] https://en.wikipedia.org/wiki/South_American_dreadnought_rac... [2] https://blog.wikimedia.org/2016/01/03/wikipedia-top-twenty/