IANAL but for me that looks like also banning the usual method of implementing your games server in Unity if we think it also bans SpatialOS.
For me the old terms look like trying to get more money from services like PlayStation Now. However if they really did forbid SpatialOS then that means every single mobile game with server implemented in Unity are also breaking the TOS and should be shut down asap.
Rergardless this debacle proves that Unity is more than willing to interprete their TOS quite liberally if they smell money. So if you build a big MMO that rakes in billions you should expect Unity to barge in and use that, or some other, part of TOS to demand more money from you.
EDIT: My hunch in how this went down. Year ago unity told them that 2.4 breaks the TOS and wanted more money. Improbable said "Nuhhuh, can't you read?" until Unity changed their TOS and said "Yeah! It does!".
So if Unity ever says that you break their TOS and they want money it's better to pay them regardless of what the TOS says because otherwise they just change the TOS retroactively.