That doesn’t track at all. Markdown was created as a simpler way to mark up text than HTML. They are both ways of encoding a document that provide ways to convey intention. HTML is no one’s end goal.
> Markdown’s syntax is intended for one purpose: to be used as a format for writing for the web. […] For any markup that is not covered by Markdown’s syntax, you simply use HTML itself.
First sentence of the announcement / introduction of markdown:
> Markdown is a text-to-HTML conversion tool for web writers.
HTML embedding was also integral to it: https://daringfireball.net/projects/markdown/syntax#html
> Markdown’s syntax is intended for one purpose: to be used as a format for writing for the web. […] For any markup that is not covered by Markdown’s syntax, you simply use HTML itself.