metaprogramming is the ability for a program to read, generate, and analyze code by itself.
what you're showing are custom blocks, which you write yourself, not the code.
for example, @ego-lay_atman-bay wrote a program to transform snap code into scratchblocks.
it reads the code inserted into the block and generates the scratchblocks equivalent.
here's a project I made that can turn blocks into text and back to blocks.