I’m a believer, give it a go!
If you connect your MacBook via HDMI to a TV it’ll work (even with a non-Stadia controller). However you’ll need a Chromecast Ultra for true 4k/60 support. Macbook’s aren’t currently 4k capable through Stadia so you’ll be limited to 1080p/60 (unless you use a third party work-around to force a higher resolution VP9 codec).