This has been discussed before in math markdown on this site, but I'd like to have some fresh discussion of this matter. Circumstances have changed in the meantime. The discussion of 2011 seems to consider it a foregone conclusion GDSE can't & won't get MathJax, but sites such as RPG Stack Exchange and Code Review and Worldbuilding have been granted MathJax, so that's no longer the case. I think it's worth having a fresh discussion of the matter; none has happened since 2011 because each subsequent time the issue has been raised it's been closed as a duplicate of that 2011 discussion. Jeff Atwood called it a heavy dependency, but that was in 2010, and MathJax's client-side performance has improved since then to be pretty smooth.
I believe it would be beneficial for GDSE to have MathJax enabled, and it's likely we could actually get it if we can show we'd benefit from it — which I am sure we can.
As Shog9 said in response to Code Review's request for MathJax:
Unless there's a large population of posts that could benefit extensively from it, there's no need to impose the cost on the rest of the posts. A few subscripts don't really necessitate this.
I believe there may well be such a large population of posts. Game development can get very mathematical: matrices, vectors, quarternions, projections, rotation, probability, physics, and graphics operations, are all mathematical subjects that are standard fare for us.
In one prior meta request, a user expressed they would prefer to use math formula, but used psuedocode because it was all that was available.
As was the case on on RPG Stack Exchange, the standard delimiter of
$ ... $ would be an issue, so we could instead use delimiters of
\$ ... \$ for inline MathJax, and
$$ ... $$ for block-level MathJax.