Cost of the OS is a large part of it.

Another is Windows FORCING reboots for updates when IT wants to do it.

A third is the “computing” overhead that Windows demands. Even running the GUI, Linux uses much less of the CPU’s time than Windows.

Ubuntu is as easy to set-up as Windows (unless you have very odd hardware/software), doesn’t force updates down your throat, frees up more CPU time and RAM for the applications YOU want to run and best of all won’t cost you a thin dime to purchase. Unless you want to make a purely voluntary donation to the developers.

You are going to need a router with a 10G WAN port and preferably a couple of 10G LAN ports, at least some 1G ports. This would also be where your main WiFi signal for the house is generated (unless the modem generates WiFi). You would connect a switch to one of the LAN ports on the Router to connect more computers via Ethernet. Note: Asus does make a router that also has a 10G LAN port (the RT-BE96U BE19000) for about $300 more than the one I linked.