Hi jedth, fellow user here.
YouTube iframes are working fine for me. Could you try pasting this embed in your page and see if it works?
<iframe
width="560"
height="315"
src="https://www.youtube.com/embed/c53sRVI4N9I"
title="YouTube video player"
frameborder="0"
allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
allowfullscreen>
</iframe>
(This is the code I get from going to the YouTube video, clicking “Share”, then clicking “Embed”.)