It was since Win XP 64bit, ~20 years ago.
You could run win16 apps on Windows 10 32bits though (supported until May 2020) https://learn.microsoft.com/en-us/windows/compatibility/ntvd...
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You could run win16 apps on Windows 10 32bits though (supported until May 2020) https://learn.microsoft.com/en-us/windows/compatibility/ntvd...