apple clang 12 vector<float> noexcept check fails

The question is very simple. I am using Apple Clang 12 and this fails:

static_assert(std::is_nothrow_move_assignable_v<std::vector<float>>);

I cannot figure out why even by navigating their macros in the source code to determine whether noexcept is truly active in my configuration (it should). It seems that depend on an internal cpp version > 14 but it is 18... not sure what else could be wrong.

Error:

    static_assert failed due to requirement 'std::is_nothrow_move_assignable_v<std::__1::vector<float, std::__1::allocator<float> > >'
static_assert(std::is_nothrow_move_assignable_v<std::vector<float>>);
^             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~