Too slow for me on Chrome.
"the tools I use recognize that structure"
Yes. I would describe it as parsing the content into a tree. Interaction's with content can then be legal operations on the tree, instead of random acts on plain text. "Us founders are blitzing 80+ hours a week."
This is where most people with a family would stop reading. "If you're young and energetic, come join us."
That is border-line ageist. The rest is a half-hearted apology that won't entice a normal person to want to work in the advertised conditions.