iOS 17.3 updates includes some critical security updates, so you should install them ASAP.
Stolen device protection increases by way of only allowing Face ID or Touch ID on some actions i.e. no passcode fallback. Also there’s Security Delay which adds a 1 hour wait between certain sensitive instructions.
AirPlay hotel support to allow streaming directly to enables TVs.
If you did the last update in iSO 17 you’ll be given the option to set the update to run tonight. So no excuses😇
Current versions are:
tvOS 17.3 & audioOS
This MacRefresh article goes into more detail.