>Why exactly is the US still in Syria?

Oil. The US has setup bases around oil fields and are stealing the oil by the tanker convoy load via Kurdistan.

https://www.washingtoninstitute.org/policy-analysis/inside-story-how-trump-kept-oil-syria-and-lost

https://www.politico.com/news/2020/08/03/delta-crescent-energy-syrian-oil-391033

https://foreignpolicy.com/2020/08/05/kurds-oil-syria-us-troops-trump/