"So, can someone remind me why
is not a good html replacement for carriage returns?"

Because it's not all about you. https://developer.mozilla.org/en-US/docs/Web/HTML/Element/br

"Accessibility concerns

Creating separate paragraphs of text using <br> is not only bad practice, it is problematic for people who navigate with the aid of screen reading technology. Screen readers may announce the presence of the element, but not any content contained within <br>s. This can be a confusing and frustrating experience for the person using the screen reader.

Use <p> elements, and use CSS properties like margin to control their spacing."