then you are almost reimplementing TCP over UDP again

you implement TCP features only when you need them. player positions for example are not critical, you can miss some but your game would still work if you are interpolating things correctly. if your player position message gets lost, you don't need it anyway you only need the newest position. same goes for order of the packets, if you are not needing such a thing, your lost packets would delay everything in the game.

For these reasons, TCP suffers a lot more if the network is bad. You really don't need to be a AAA company to implement TCP features on UDP.

  UDP's only point in this article is realtime data intensive games like FPS'es.

Well article says, as you quoted:

> It would greatly improve the networking of these games.

And 'these games' are he means real time games like agario. It is not a FPS but it is a real time game. There is no reason to use UDP if it is a turn based game, like a card game. But a real time is pretty much always would be better with UDP