This is not about where US troops are stationed. The two thousand US soldiers at issue are a drop in the bucket in terms of the number of armed fighters in Syria today. They have not been on the frontlines of the fighting the way that the US military was in Iraq.
The withdrawal of these soldiers is not the important thing here. What matters is that Trump’s announcement is a message to Erdoğan indicating that there will be no consequences if the Turkish state invades Rojava.
An Anarchist in Syria in Crimethinc. he Threat to Rojava
An Anarchist in Syria Speaks on the Real Meaning of Trump’s Withdrawal