Unity 2018 - Capable of an MMOFPS 900-1200 players possible?

Nah, I'm good. I was trying to dig into that stuff to spur on the thoughts, ideas and methods you asked for.

 

Just thinking about the networking side of things and wondering do the internet protocols allow the servers to send out a single packet of updates to multiple IPS or combine incoming packets to the server from multiple IPS?

 

Yes, there is support for broadcast and multicast transmissions in IP protocol. Most IP stuff is done using unicast, though. The one limitation of broadcast support is it is for broadcasting to an entire network range instead of a diverse list of connected clients. Most live streaming media on local subnets is supported using multicast. Note that UDP multicast is generally not routed across the Internet, though.