I strongly support inclusion of Pandoc-style inline math notation, with at least the status of “you don’t have to do anything with this, but you must still parse it correctly”. For instance, in
Let $y = m * x + b$ where $b$ is US$50,000
the asterisk in m*x should not be interpreted as an emphasis marker, and conversely, the dollar sign in US$50,000 should not be interpreted as a math shift.
Displayed equations are more complicated — I’m not a mathematician, and yet, in every paper I’ve written that had even a little math in it, I’ve found myself reaching for \begin{align*} and friends from amsmath. As such, I would prefer fenced-block syntax for display math, with implementation of the full amsmath repertoire of math environments encouraged.
Note further that displayed math can plausibly have text nested inside it, with inline math nested inside that:
```equation
a(t) = \begin{cases}
a_0 \sin kt & \text{when $a > 0$} \\
0 & \text{otherwise} \\
\end{cases}
```
and it’s not out of the question that someone would want to put inline markdown markup inside \text{...} as well.