Javascript использовать одну функцию для нескольких идентификаторов

Вот быстрый макет того, как думаю вы должны это делать. Не проверено, возможны опечатки и т. д.

<?php
$paragraphs = []; // create an empty array we will put our two paragraphs into

// define your two paragraphs/text-items with everything that's unique to them:
$paragraph = new stdClass();  // just creates a simple object we can fill with infos
$paragraph->elementId = "dyn_Loop_main_v1";  // the id of the related html element
$paragraph->updateTime = 1500;  // how quick it should switch to next text in ms
$paragraph->content    = array("TEXT for ID_1_1",
                            "TEXT for ID_1_2",
                            "TEXT for ID_1_3",
                            "TEXT for ID_1_4");
$paragraph->default = "Default Text 1";
$paragraphs[] = $paragraph; // add this paragraph to the array
// same for the second paragraph:
$paragraph = new stdClass();
$paragraph->elementId = "dyn_Loop_main_v2";
$paragraph->updateTime = 1000;
$paragraph->content    = array("TEXT for ID_2_1",
                            "TEXT for ID_2_2",
                            "TEXT for ID_2_3",
                            "TEXT for ID_2_4");
$paragraph->default = "Default Text 2";
$paragraphs[] = $paragraph; // add this paragraph to the array

// you could now also create those 2 elements dynamicly via php:
foreach($paragraphs as $paragraph) {
   echo "<span id='{$paragraph->elementId}'>{$paragraph->default}</span>\n";
}
// OR write them hardcoded:
?>
    <span id = "dyn_Loop_main_v1">Default TEXT 1</span>
    <span id = "dyn_Loop_main_v2">Default TEXT 2</span>
<?php

// now let's transfer our paragraphs to javascript so that we can continue there:
?>
<script>
var paragraphs = <?php echo json_encode($paragraphs, JSON_PRETTY_PRINT); ?>;
</script>

При синтаксическом анализе это должно выглядеть так ("исходный код"):

var paragraphs = [
    {
        "elementId": "dyn_Loop_main_v1",
        "updateTime": 1500,
        "content": [
            "TEXT for ID_1_1",
            "TEXT for ID_1_2",
            "TEXT for ID_1_3",
            "TEXT for ID_1_4"
        ],
        "default": "Default Text 1",
        "counter": 0
    },
    {
        "elementId": "dyn_Loop_main_v2",
        "updateTime": 1000,
        "content": [
            "TEXT for ID_2_1",
            "TEXT for ID_2_2",
            "TEXT for ID_2_3",
            "TEXT for ID_2_4"
        ],
        "default": "Default Text 2",
        "counter": 0
    }
];

И вот основная часть javascript:

<script>
// define a function that updates the paragraphs and increases the counter.
// it takes one paragraph object as parameter.
function updateParagraph(paragraph) {
  document.getElementById(paragraph.elementId).innerHTML = paragraph.content[paragraph.counter];
  paragraph.counter++; // set counter up
    // if we've reached the end, reset to start:
  if (paragraph.counter>=paragraph.content.length) { 
    paragraph.counter = 0;
  }
}

// let's call that function with our first paragraph as parameter with the updateTime defined in an Interval:
setInterval(function() {
      updateParagraph(paragraphs[0]);
   },
   paragraphs[0].updateTime
);

// repeat for second:
setInterval(function() {
      updateParagraph(paragraphs[1]);
   },
   paragraphs[1].updateTime
);
</script>

Последняя часть может / должна, конечно, также стать динамической, поэтому вызывается / настраивается автоматически для каждого абзаца следующим образом:

paragraphs.forEach(function(paragraph) {
  console.info(paragraph); // just checking what we've got here
  setInterval(function() {
         updateParagraph(paragraph);
      },
      paragraph.updateTime
  );
});

Скрипка для части php: https://3v4l.org/fp68u
Скрипка для части Javascript: https://jsbin.com/nuxejutiga/edit?html,js,output