I have recently acquired a small swimming pool, and my wife has taught me the expression to “flocc and shock” for removing debris. This appears to be the etymology

“Flocculant” isn’t a product name, it’s a description of the function of an agent (like a “detergent” that makes a liquid less turgid). A flocculant will clump the fine particles together so the clumps will be large enough to be strained out.

The difference isn’t that it’s using fancy technology, it’s that the product is standardized and fully proven via real world clinical trials.