It isn't that Mulu is a big mountain. At a shade under 8,000 feet, its mere statistics would not put off the average weekend hill walker. But
there is more to this mountain than a set of figures. In the words of a
popular guide book: "Mulu National Park may now have an airport
and a first-class hotel, but its mountain proves that Borneo is still
Borneo." Here, there are still frontiers beyond the established tourist
trails.

5. What does the writer mean when he says: 'its mere statistics would not put
off the average weekend hill walker'?

The writer by saying 'its mere statistics would not put  off the average weekend hill walker' simply means that, despite the fact that, Mulu mountain seems to have a moderate height of 8000 feet which would discourage some people to climb, it is nevertheless, still a mountain worth climbing for which always attract tourists to it. This tourists always came in the weekend in-order to be able to partake in the hill climbing.

Explanation:

answer: the sentence in the text that contains both the topic and the author's single most important idea about the topic

explanation: aww pineapple so adorable