Is it possible to make an HTML anchor tag not clickable/linkable using CSS?

You can use this css:

.inactiveLink {
   pointer-events: none;
   cursor: default;
}

And then assign the class to your html code:

<a style="" href="page.html" class="inactiveLink">page link</a>

It makes the link not clickeable and the cursor style an arrow, not a hand as the links have.

or use this style in the html:

<a style="pointer-events: none; cursor: default;" href="page.html">page link</a>

but I suggest the first approach.