Seriously, how can the most used game engine not add proper multiplayer support in 20 years. They announced Netcode for game objects this year which seems OK but even that has "Clientside prediction" in "under consideration" category, any proper realtime multiplayer game on the market has this feature and rollback netcode isn't even under consideration. So if they achieve their goals, they will have a system that is good for at most indie games after 20 years.