In reply to Otto.

Sometimes a single paragraph might be a block, but more often we regard a group of several paragraphs as a block.
We commonly move small sub-sentence phrases around within the multi-paragraph block using cut, copy and paste to improve our phrasing and meaning.
A paragraph-spanning selection, with cut copy paste editing is common across text editing software but is not possible in Gutenberg as paragraphs are now each in their own editor and selections cannot span them.

The line-based content editing issue was considered/raised at the very start of Gutenberg's creation and has been raised many times since.
I suggest it would be better if consecutive paragraphs are monolitic unless the user initiates a splitting action (inserts media at the caret, activates a splitting action)