No one is actually pulling out. The U.S. has made it harder for foreign companies to import them. But there are still domestic manufacturers of EVs, like Tesla, Ford and Stellantis. This is something very else: For the last decade, one big argument against EVs was "bad resale value", because EVs were seen as a novelty, and fear for dead batteries, fueled by the problems with first gen Nissan Leafs, made buyers wary of used EVs. Additionally, there were not many used EVs on the market to begin with, fleet operators did not have many young EVs to sell, and prices did not really average out yet.
Now, demand for EVs is rising due to high fuel prices, and a good public charging network making EVs a viable alternative for many people. And also people looking for bargains are hitting the market, and with used batteries not being the problem they were thought to be, used EVs have its own value proposition. We have here the normal effect of demand rising more than the available supply.