Who told him that? Developers like myself who recognize that most frameworks -- PARTICULARLY on the front end make you write more code, more complex code riddled with specificity hell, and in fact do NOT make it any easier, or "save developer time" or any of the other BULLSHIT ignorant claims made about them.
Said claims clearly being ignorant nonsense if you take the time to bother learning to use HTML and CSS properly in the first place with semantic markup, separation of presentation from content, leveraging selectors, and all the other good practices we've been told for near on two decades to use that large swaths of users still flat out ignore.
Since if you don't know what's wrong with this:
<div class="w3-top">
<div class="w3-bar w3-black w3-card">
<a class="w3-bar-item w3-button w3-padding-large w3-hide-medium w3-hide-large w3-right" href="javascript:void(0)" onclick="myFunction()" title="Toggle Navigation Menu"><i class="fa fa-bars"></i></a>
<a href="#" class="w3-bar-item w3-button w3-padding-large">HOME</a>
<a href="#band" class="w3-bar-item w3-button w3-padding-large w3-hide-small">BAND</a>
<a href="#tour" class="w3-bar-item w3-button w3-padding-large w3-hide-small">TOUR</a>
<a href="#contact" class="w3-bar-item w3-button w3-padding-large w3-hide-small">CONTACT</a>
<div class="w3-dropdown-hover w3-hide-small">
<button class="w3-padding-large w3-button" title="More">MORE <i class="fa fa-caret-down"></i></button>
<div class="w3-dropdown-content w3-bar-block w3-card-4">
<a href="#" class="w3-bar-item w3-button">Merchandise</a>
<a href="#" class="w3-bar-item w3-button">Extras</a>
<a href="#" class="w3-bar-item w3-button">Media</a>
</div>
</div>
<a href="javascript:void(0)" class="w3-padding-large w3-hover-red w3-hide-small w3-right"><i class="fa fa-search"></i></a>
</div>
</div>
You likely have ZERO damned business writing a single damned line of HTML or CSS!!! Endless pointless DIV for NOTHING, endless pointless classes for NOTHING, and NOTHING remotely resembling semantic markup resulting in the menu reading as a run-on sentence in screen readers/braille readers/search engines. EPIC /FAIL/ at web development!
100% grade A farm fresh ignorant halfwit dumbass derpitude that only someone who failed to grasp the point of 4 Strict, the point of semantics, and the ENTIRE reason HTML and CSS are separate would be STUPID ENOUGH to do in the first place!
Which is how the ignorant twaddles duped into using that sort of garbage end up vomiting up TWICE the HTML heeded:
<div id="top">
<input type="checkbox" id="mainMenuShowHide">
<label for="mainMenuShowHide">
<ul id="mainMenu">
<li><a href="#">HOME</a></li>
<li><a href="#band">BAND</a></li>
<li><a href="#tour">TOUR</a></li>
<li><a href="#contact">CONTACT</a></li>
<li>
<input type="checkbox" id="moreMenuShowHide">
<label for="moreMenuShowHide">More</label>
<ul id="moreMenu">
<li><a href="#">Merchandise</a></li>
<li><a href="#">Extras</a></li>
<li><a href="#">Media</a></li>
</ul>
</li>
</ul>
<a href="#searchModal">🔍</a>
</div>
To do the exact same job -- because they're too stupid to leverage selectors and use HTML or CSS properly. THEN they try to claim writing as much if not more code is "easier" -- BULLSHIT!
People are diving for frameworks before they have sufficient command of the underlying languages to ACTUALLY know if any of them -- bootcrap, w3.css, jQuery, react, whatever -- are ACTUALLY easier, simpler, or ACTUALLY helps with collaboration.
Which when these stupid dipshit HTML/CSS frameworks create specificity hell, piss on the markup from orbit with presentational classes, and result in writing two to ten times the code needed to do the job NOT counting the size of the framework against it, HOW IN THE BLUE BLAZES IS THAT EASIER?!?
But people blindly parrot "easier" and "collaboration" because that's all you ever hear about them, and like Goebbels "big lie" you repeat it loudly enough and often enough and echo-chamber the feeble minded into repeating it, "it must be true" even when it clearly isn't.
Hence why if you don't know what's wrong with this mental midgetry:
<div class="w3-bar-block w3-black w3-hide w3-hide-large w3-hide-medium w3-top" style="margin-top:46px">
You might as well go back to writing HTML 3.2 with tables for layout and pretend CSS doesn't even EXIST as you've CLEARLY failed to grasp the simplest of the concepts of HTML 2, HTML 4 strict, or what CSS is even FOR!