The API lets you directly choose the model you want. Automatic thinking is a ChatGPT feature since ChatGPT has always been a “GPT wrapper” in that sense.
I don't think the dialog as described in the article is accurate and I can't find a screenshot of Windows NT that says "Windows has been shut down." The only screenshots I can find say, "It is now safe to turn off your computer." The confusion around the Restart button is understandable, but the framing of the story seems to imply that the old dialog led to the later phrase, "It is now safe to turn off your computer."