That would be

<DoStuff args={...}><DoMoreStuff args={...} /></DoStuff>

Still more readable than brackets hell like:

DoStuff(DoMoreStuff(DoEvenMoreStuff()))

^^^ Apples to oranges:

    <DoStuff args={...}><DoMoreStuff args={...}> <DoEvenMoreStuff args={...}/> </DoMoreStuff> </DoStuff>

vs

    DoStuff(DoMoreStuff(DoEvenMoreStuff()))

Both of them you would split into indented lines when they become too long. And 1 becomes too long much faster.

Also with 2 you can do

    const todo = DoMoreStuff(DoEvenMoreStuff());  
    DoStuff(todo);

where as with 1 you cannot.

With JSX you can do

  const todo = <DoMoreStuff args={...}><DoEvenMoreStuff args={...}/></DoMoreStuff>;
  <DoStuff args={...}>{todo}</DoStuff>