I'd kinda like all machines to do this all the time...
The OS should go to sleep, and give the network hardware enough info to respond to simple requests (ie. maybe ARP requests, mDNS, and keeping a DHCP lease alive). Anything that comes in addressed to the machine that can't be handled by the network hardware should wake the machine, leaving the packet in a buffer for the machine to handle and then go back to sleep.
The OS the one-laptop-per-child machine used was capable of this - it could sleep, with the screen either on or off, between keystrokes and network packets. Lots of the network stack was moved into the always-on network hardware, so it could for example participate in the mesh network while powered off.
Sadly the whole project folded (for mostly non-tech reasons), taking most of it's cool tech with it.
Android can do this - the linux kernel goes into suspend-to-ram while the network is still up. If someone sends you a tweet, the cloud messaging service wakes the OS with a TCP packet, which eventually causes the "ding" notification that Musk has said something again...
I think this is what Modern Standby aka "S0" power state is doing. Worse it is not always properly implemented and laptops turn on burning hot in backpacks (looking at you Lenovo Legion).
The OS should go to sleep, and give the network hardware enough info to respond to simple requests (ie. maybe ARP requests, mDNS, and keeping a DHCP lease alive). Anything that comes in addressed to the machine that can't be handled by the network hardware should wake the machine, leaving the packet in a buffer for the machine to handle and then go back to sleep.