Optimization is really necessary, especially for older devices.
Performance issues in some clients and excess data usage can make it a poor quality experience and expensive to run on a metered connection.
One feature I'm looking for is a micro node to run in the background of each client device to speed it up and reduce duplicate downloads. I know nostr:npub1gcxzte5zlkncx26j68ez60fzkvtkm9e0vrwdcvsjakxf9mu9qewqlfnj5z is looking into / working on this for Amethyst.