On the topic of terminology I'll say again that the label "patterns" for laypeople means either:

A plural noun: "patterns" a repeated decorative design. "a neat blue herringbone pattern", "A check pattern". Or, a verb "to pattern" to decorate with a repeated design.

Most laypeople will not expect the tab marked "patterns" to contain layout chunks. Most laypeople will expect a "pattern library" to contain geometric patterns. In the context of a design and layout tool where we have colours, gradients and patterns - think about what the implication is.

If Gutenberg is a tool for programmers then "Patterns" is the right label. If gutenberg is a tool for laypeople then the correct label might be "Layout Chunks" or "Template Sections" something like that.

A Design Pattern in the sense of a reusable solution is industry jargon.