Why do you think server-side rendering (or transferring tags back and forth as you unconsciously grazed the solution) requires whole-page loads? Hotwire, Htmx

Why do you think server-side rendering (or transferring tags back and forth as you unconsciously grazed the solution) requires whole-page loads? Hotwire, Htmx and similar solutions allow you to simply load whatever's changed, no need for reloading an entire page or having jarring transitions.