So more like they identified that part of the known population was a different species just now. It'll take more effort tagging and identifying other tiger cats to see if they also belong to this particular one?
That said in 2020 there was an article proposing to split Leopardus colocolo in other 3 to 5. This article worked on the proposal, validating four new species more with L. tilcayo that was closer to L. tigrinus. National Geographic (as in other cases) embellished the history a little. Five new species of cats were disclosed, and four were described previously inside a species complex.
This effort is actually already ongoing. This splashy headline that seems to have crushed it on publicity front is actually just a small piece of the research currently being done on oncillas (aka tiger cats). The word on the grapevine for the past year or so is that the oncillas are going to get divided up into between five and twelve new species.