Solution 1 :

Instead of using scale() for the entire element, work with the background-size property, that way font-size will remain untouched, lemme know if it works for you or not.

.bg {
  width: 400px;
  height: 240px;
  margin: 30px auto;
  background: url(https://api.time.com/wp-content/uploads/2020/07/jeff-bezos.jpg?quality=85&w=1024&h=628&crop=1) no-repeat center center;

  background-size: 100%; /* work with the background-size */

  transition: background-size 1s ease-in-out;
  position: relative;
  z-index: 1;
}

.bg:hover {
  background-size: 120% /* work with the background-size */
}


.bg::before {
  position: absolute;
  content: '';
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,.5);
  top: 0;
  left: 0;
  z-index: -1;
}

.bg h2 {
  text-align: center;
  font-size: 60px;
  line-height: 230px;
  font-family: sans-serif;
  color: #fff;
}
<div class="bg">
  <h2>WHO</h2>
</div>

Solution 2 :

Thats the expected behavior of scale, it scale every children too, to change just the bg maybe you should use other approaches.

I provide one, I hope it fit in your need.

On this approach the BG is an absolute element, isnt the container of the h1 and the hover now is on split-image-link instead of zoom-image.

* { margin: 0; padding: 0; }
body {
}
.article-container {
    width: 300px;
    height: 200px;
    border: 1px solid #000000;
    overflow: hidden;
    position: relative;
}

.article-img-holder {
    width: 100%;
    height: 100%;
    background: url(https://awik.io/demo/background-image-zoom/traffic2.jpg);
    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;
    transition: all 1s;
}

.article-img-holder:hover {
    transform: scale(1.2);
}

.split-image-links {
    width: 100%;
    height: 100vh;
    display: flex;
}
.split-image-links .split-image-link {
    width: 25%;
    height: 100%;
    overflow: hidden;
    position: relative;
}
.split-image-links .split-image-link .zoom-image {
    width: 100%;
    height: 100%;
    cursor: pointer;
    position: relative;
}
.split-image-links .split-image-link .zoom-image .split-image-header {
    z-index: 1;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    top: 0;
    margin: auto;
    color: #fff;
}
.split-image-links .split-image-link .zoom-image-headline {
    position: relative;
    color: #fff;
    text-align: center;
    line-height: 100vh;
    font-family: 'Poppins';
    text-transform: uppercase;
    font-size: 45px;
    font-weight: 600;
}
.split-image-links .split-image-link .zoom-image.zoom-image-first {
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    margin: auto;
    background: linear-gradient(
          rgba(0, 0, 0, 0.4), 
          rgba(0, 0, 0, 0.4)
        ), url(https://api.time.com/wp-content/uploads/2020/07/jeff-bezos.jpg?quality=85&w=1024&h=628&crop=1);
    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;
    transition: all 0.5s;
}
.split-image-links .split-image-link:hover .zoom-image {
    transform: scale(1.1);
}
<body>
    <div class="split-image-links">
        <div class="split-image-link">
            <div class="zoom-image zoom-image-first"></div>
            <h1 class="zoom-image-headline">who</h1>
        </div>
    </div>
</body>

Solution 3 :

Here is the basic version of your need.

.content {
  position: relative;
  /* border: 1px solid red; */
  display: inline-block;
}

h1 {
  color: #FFF;
  margin: 0;
  position: absolute;
  top: 50%;  
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 999;
}

.bg:hover, h1:hover + .bg {
  transform: scale(1.1);
  transition: all 1s;
}
<div class="content">
  <h1>WHO</h1>
  <img class="bg" src="https://awik.io/demo/background-image-zoom/traffic2.jpg" alt="background image">
</div>

Problem :

I want to zoom background image on a hover but without change text size. How can I make this?

* { margin: 0; padding: 0; }
body {
}
.article-container {
    width: 300px;
    height: 200px;
    border: 1px solid #000000;
    overflow: hidden;
    position: relative;
}

.article-img-holder {
    width: 100%;
    height: 100%;
    background: url(https://awik.io/demo/background-image-zoom/traffic2.jpg);
    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;
    transition: all 1s;
}

.article-img-holder:hover {
    transform: scale(1.2);
}

.split-image-links {
    width: 100%;
    height: 100vh;
    display: flex;
}
.split-image-links .split-image-link {
    width: 25%;
    height: 100%;
    overflow: hidden;
    position: relative;
}
.split-image-links .split-image-link .zoom-image {
    width: 100%;
    height: 100%;
    cursor: pointer;
    position: relative;
}
.split-image-links .split-image-link .zoom-image .split-image-header {
    z-index: 1;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    top: 0;
    margin: auto;
    color: #fff;
}
.split-image-links .split-image-link .zoom-image .zoom-image-headline {
    color: #fff;
    text-align: center;
    line-height: 100vh;
    font-family: 'Poppins';
    text-transform: uppercase;
    font-size: 45px;
    font-weight: 600;
}
.split-image-links .split-image-link .zoom-image.zoom-image-first {
    background: linear-gradient(
          rgba(0, 0, 0, 0.4), 
          rgba(0, 0, 0, 0.4)
        ), url(https://api.time.com/wp-content/uploads/2020/07/jeff-bezos.jpg?quality=85&w=1024&h=628&crop=1);
    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;
    transition: all 0.5s;
}
.split-image-links .split-image-link .zoom-image:hover {
    transform: scale(1.1);
}
<body>
    <div class="split-image-links">
        <div class="split-image-link">
            <div class="zoom-image zoom-image-first">
                <h1 class="zoom-image-headline">who</h1>
            </div>
        </div>
    </div>
</body>

Comments

Comment posted by Zoom background image only

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