What’s the best server for gaming in a house full of gamers?

I’ve got three roommates. We’re all gamers. We’re also all tired of random lag spikes, desyncs, and friends dropping out mid-match because someone decided to stream 4K cat videos. Thinking of building a centralized game server in the living room (or maybe the closet?) Idea is to run game servers locally, maybe even cache updates, or try some kind of peer LAN streaming for co-op sessions.

Anyone here tried something like this? I’m curious what kind of specs actually matter (CPU cores? RAM? Disk I/O?) Latency is obviously key, but beyond that, what makes a great “home gaming server”?