I still believe there are traders who leave their assets on the exchanges, although it may not be a large amount for traders. They do not want to be burdened with withdrawal fees that would become quite uncomfortable if done continuously at the end of the trading session.
I think it's very reasonable for traders nowadays to have several exchanges that are indeed their favorite places to trade, whether for the purpose of taking advantage of them to make a profit or simply because they are comfortable choosing one or several exchanges for other reasons.
That certainly exists, and we ourselves may even employ such a strategy because it's impossible to withdraw all our assets at the end of a trade due to the inconvenient withdrawal fees for each transaction. While this may seem reasonable, everyone has their own perspective, but when it comes to asset storage, we must agree that exchanges are not a safe place to store them. A small amount of our assets are certainly stored on exchanges as part of our transactions, and perhaps when trading, we don't have the hassle of transferring them from our wallet to the exchange every time. In my opinion, that's perfectly normal and not a major issue.