None of those features require LaTeX arcane syntax, obscure source code, and multiple compilation steps. reStructuredText is a Markdown-like language containing some of the features you mention, especially with extensions; its syntax is well-defined, and its main implementation is in Python.
The point isn't if Markdown has enough features, but rather that LaTeX lets you a pay a price for those features that you shouldn't be paying, just because it's a 40-years-old software.
The point isn't if Markdown has enough features, but rather that LaTeX lets you a pay a price for those features that you shouldn't be paying, just because it's a 40-years-old software.