That statement basically only applies for おる as a simple existence verb. Non-humble おる is very common in Kansai. As a subsidiary verb, various forms including とる/ちょる/よる are commonly used instead of standard (~て)いる, but there are considerable regional variations even inside Kansai. See this discussion.
- 太郎はおる。
There is Taro. / Taro is here. (≒太郎はいる)
- 太郎は来とる。
[Chugoku/Shikoku] Taro has (already) arrived. (≒太郎は来ている)
[Osaka/Kyoto] Taro is (now) coming. / Taro has (already) arrived. (≒太郎は来ている)
- 太郎は来よる。
[Chugoku/Shikoku] Taro is (now) coming. (≒太郎は来ている)
[Osaka/Kyoto] (Damn,) Taro will come! (≒太郎は来やがる)
おる does not replace ある for inanimate objects. 本がおる is incorrect. (The article says the opposite (先生がある) happens in parts of Wakayama, but I'm not familiar with that.)