[Malleys]

Можно сделать при помощи маски, тогда только у текста будет уменьшаться непрозрачность.

<section>
	<p>Lo­rem ip­sum do­lor sit amet con­sec­te­tur adi­pi­si­cing elit. Est ve­ro ve­ri­ta­tis, mo­di hic nam ac­cu­san­tium ma­xi­me mi­nus. Re­rum tem­po­ra li­be­ro, od­io ni­si ve­ri­ta­tis de­le­ni­ti in­ven­tore quas ac­cu­san­tium do­lo­res dic­ta ea!</p>
	<button>Read more</button>
</section>
<style>
section {
	background: black;
	color: white;
	padding: 1em;
	position: relative;
	font-size: 150%;
	background: linear-gradient(to bottom, rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url(https://picsum.photos/200/300/?blur=2) center/cover;
	max-width: 15em;
}

section > p {
	--mask: linear-gradient(to bottom, red 10%, transparent);
	-webkit-mask: var(--mask);
	mask: var(--mask);
	margin: 0;
	text-indent: 0.5em;
	text-align: justify;
}

section > button {
	all: unset;
	position: absolute;
	bottom: 1.5em;
	right: 0; left: 0;
	margin: auto;
	background: linear-gradient(to bottom, #3f749b, #78a5cc);
	padding: 0.25em 0.75em;
	border-radius: 1em;
	text-shadow: 0 1px rgba(0, 0, 0, 0.5);
}
</style>

Или же поместить градиент над текстом, что затронет также и фон.

<section>
	<p>Lo­rem ip­sum do­lor sit amet con­sec­te­tur adi­pi­si­cing elit. Est ve­ro ve­ri­ta­tis, mo­di hic nam ac­cu­san­tium ma­xi­me mi­nus. Re­rum tem­po­ra li­be­ro, od­io ni­si ve­ri­ta­tis de­le­ni­ti in­ven­tore quas ac­cu­san­tium do­lo­res dic­ta ea!</p>
	<button>Read more</button>
</section>
<style>
section {
	background: black;
	color: white;
	padding: 1em;
	position: relative;
	font-size: 150%;
	background: linear-gradient(to bottom, rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url(https://picsum.photos/200/300/?blur=2) center/cover;
	max-width: 15em;
}

section > button {
	all: unset;
	position: absolute;
	bottom: 1.5em;
	right: 0; left: 0;
	margin: auto;
	background: linear-gradient(to bottom, #3f749b, #78a5cc);
	padding: 0.25em 0.75em;
	border-radius: 1em;
	text-shadow: 0 1px rgba(0, 0, 0, 0.5);
}

section > p {
	margin: 0;
	text-indent: 0.5em;
	text-align: justify;
	position: relative;
}

section > p::after {
	content: "";
	position: absolute;
	top: 0; left: 0; right: 0; bottom: 0;
	background: linear-gradient(to bottom, transparent, black);
	margin: -1em;
	pointer-events: none;
}
</style>