Can confirm. Coax cabling in North American homes is really common. It was intended for running cable TV from your cable boxes to other rooms. Ethernet is rare

Can confirm. Coax cabling in North American homes is really common. It was intended for running cable TV from your cable boxes to other rooms. Ethernet is rare. My current place also has coax everywhere. Like you, I use this for wired networking. So the only thing I'll add is if you do run cable TV over coax in your house you'll need to use MoCa splitters if you want to run wired networking too. Splitters are cheap. You can buy them on Amazon. If you don't run cable TV you don't need splitters. I would also advise you pay about $40 for a test kit to test your cable. I also needed this to find out where cables terminated to a central repeater. I don't know what speeed I could get but I have nothing about gigabit ethernet and it runs to that speed (~930Mbps) just fine.