There is very low likelihood that the United States will be a net exporter of petroleum. The article might be misinterpreting the IHS report, as I have not seen it.
Perhaps at some time the US may be a net energy exporter which includes petroleum, natural gas liquids, natural gas and refined products, but not for just petroleum.
The long term prognosis for petroleum production is not all that great, notwithstanding the extrapolation of current trends of Permian and other unconventionals production. The extrapolation runs smack up against the technical realities of there being enough in resources to make it happen.
BTW, a lot of the current production from unconventionals of what is called petroleum is not petroleum at all, but instead is natural gas liquids or condensates. That is one area where the article breaks down a bit.
To be considered petroleum, it must be liquid in situ.
Perhaps the petroleum demand forecast is where the article's author surmises we will have abundant petroleum to export.