Correct, Smartthings does not.
Which SmartThings devices work with the Google Assistant?
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The Google Assistant can control light bulbs, plugs, on/off switches, dimmers, and thermostats found on our Works with SmartThings page.
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Google Assistant can also queue contact sensors and temperature sensors for their current state. For example, if you have a contact sensor or a temperature sensor on your front door, you can ask Google if the front door is open or what the temperature is.
If you are using the classic V2 app, you can get around that by putting your desired action in a smart things routine, triggering that routine from a virtual switch, and having Google turn the virtual switch on and off.
But that doesn’t work with the new V3 app. 
( I am quadriparetic, so hands-free operation of locks was the very first thing that ever brought me to home automation. The loss of this feature with the V3 app is very concerning to me.)