<p>: The Paragraph element
The <p> HTML element represents a paragraph. It is one of the most common semantic HTML elements.
Recommendation
It is highly recommended for an email client to support the <p> element.
Impacts
Accessibility
Assistive technology including screen-readers understand what the <p> is meant to represent which allows them to provide their users with a way to perform common reading tasks such as skipping a paragraph and navigating to the next/previous paragraph.