Why no mathematical sans-serif capital theta?

Is there a good reason, or some explanation, for the lack of
MATHEMATICAL SANS-SERIF CAPITAL THETA in Unicode?

As far as I have understood, the Mathematical Alphanumeric Symbols block
has been added to make it possible to make certain distinctions at the
character level. The difference between serif and sans-serif is mostly
stylistic, not a character-level issue, but for some identifiers, it has
been defined as an essential difference. In mathematics, tensors are
denoted by sans-serif symbols, and in physics, identifiers for
dimensions are denoted by capital sans-serif letters (e.g., L stands for
length, T for time).

Since the standard symbol for thermodynamic temperature in dimension
notations is Greek capital letter theta Θ, and since these notations are
to use sans-serif font, I would expect to find MATHEMATICAL SANS-SERIF
CAPITAL THETA.

Surprisingly, MATHEMATICAL SANS-SERIF BOLD CAPITAL THETA (U+1D75D) and
MATHEMATICAL SANS-SERIF BOLD ITALIC CAPITAL THETA (U+1D797)exist, so why
was the normal (non-bold non-italic) symbol omitted?

-- 
Yucca, http://www.cs.tut.fi/~jkorpela/