I never thought I would connect my Hisense to the internet, but it turns out that it runs an MQTT broker and responds to WoL packets, so control via Home Assistant was really easy to setup and is much better than the IR blaster I was using before as response is almost instant and I can get power state so I can sync it to the rest of my living room. Most smart TVs seem to do well behind a DNS black hole, and if you're knowledgeable enough for that then self-hosting a dnsmasq instance on an old box you have lying around and pointing the TV at it is a snap.