Rendering thousands of DOM nodes is expensive because:

[elite-dev9]

• Layout & paint cost: Browsers calculate styles and layouts for every visible and hidden element.
• Memory usage: Every DOM node consumes memory; large trees can cause GC pressure.
• Event binding & reconciliation: React/other frameworks diff large virtual DOM trees, increasing CPU usage.
• Reflow & repaint on interactions: Any UI change triggers browser reflows and repaints, which become slow for huge DOMs.

[GenuineGenius999]

Oh, is this answer?
Then you might be right...
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