> This animal figure is represented as a pictorial outline shown in side (profile) view with an infill pattern consisting of painted strokes or lines. It is therefore consistent in style with the visual convention used to represent pigs and other animals in the dated Late Pleistocene rock art of South Sulawesi, including at Leang Bulu’ Sipong 4 [1]

They base the interpretation off of other cave art in the area that's better preserved [2] and the fact that it's missing facial details of other animals found in the local cave art [3].

There's usually other context in archaeological speak, like buried bones and fossils that limit the possibilities.

[1] https://www.nature.com/articles/s41586-024-07541-7

[2] https://www.bradshawfoundation.com/bfnews/uploads/sulawesi_p...

[3] https://cdn.sci.news/images/enlarge6/image_7902_1e-Leang-Bul...

I'd say the pig is somewhat recognizable, with four legs and a tail. The humans on the other hand...

"A pig? Looks like two bears high-fiving to me."