Ten years ago, that may have been valid advice, when &quot;dynamic&quot; mostly meant &quot;server-generated&quot;. But if you&#x27;re creating a website that is heavily JS-based, it does no good to serve 25% of your customers a perfectly-standards-compliant page telling them their JS won&#x27;t work, so the site can&#x27;t do its thing. You still need to know what client base you are supporting, no matter what.