This is exactly what I am talking about
: an option
you can enable or disable, nothing more, nothing less!
By the way, if you need to put a space after a heading you could use, in the CSS, the function "margin-bottom: 2em;"
It allows you to precisely adjust the space between these two elements (h1 and the next paragraph).
The problem with empty paragraphs as a space (something like that "<p class="p1"> </p>") is especially noticeable at the end of a file: an eReader can put a blank page after it, which is not necessarily desirable.
Personally, I never use empty paragraphs in the epub (and very rarely in document files): it seems much more efficient and judicious for me with styles and CSS.
Have a very nice evening Montyp535!