The margin in the King James Version suggest ‘I pray’ rather than ‘I wish’, and that actually is a much better idea and translation of what John intended to say. ‘I pray above all things that thou mayest prosper.
Oh I trust we can say that of everyone. We want you to have good health and reasonable well-being. Do not pray that you will wealthy: that may not be good for you, may ruin you, may spoil you. We are grateful for some people who have wealth and deploy it sensibly and well for the things of God, but many of us would be spoiled by it, so do not pray for wealth. But yes, for well-being, for adequate provision, for enough to be good Christian people and to serve the Lord. That is all we ask. And health, yes. Not just for its own sake but so that the life will be for the Lord.