You either use TCP or re-implement TCP over UDP i.e. QUIC
So in a real-life example, this is like a movie-ticket seller optimizing the ball bearings in a shopping cart that you need to buy those tickets, because they want you to carry a bunch of flyers and gps trackers with you, while all you need is a small paper ticket.
Then in a few generations when the world comes back to its senses, some historian will find it and laugh at how dumb and broken our generation was.