it would, just without standard library support, as the default stdlib imports system APIs that older versions don't provide. Other than those and a "supported OS version" filed in the PE header there isn't really much else in your way (hence my Rust9x project)

I thought win16 only supported NE and MZ, does it support PE?

this comment thread hasn't been talking about win16.

but you're right, win16 can only load some 32-bit PE files through something like Win32s