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.
AFAIK, Netcode for game objects is merely a rebranded version of a previously existing third party plugin called MLAPI that Unity acquired and hired its developer.
It is very close to what they already had before and was probably mostly to reduce the amount of complaints from, well everybody, regarding their non existent multiplayer, the deprecation of their previous multiplayer solution (however bad) before having any sort of replacement and the semi recent addition of the low-level networking solution that is mostly way too complicated and poorly documented for most average Unity developers.