Strong evidence that a search algorithm can find high functionality in an astronomically large search space

You keep appearing to assume that functional proteins are randomly distributed in search space.

This is not the case - for example, average globular protein consists of ~31% alpha helices and ~28% beta sheets.

https://www.letstalkacademy.com/publication/read/protein-structure-protein-secondary-structure-protein-beta-sheet

If virtually all functional proteins have alpha helices and beta sheets, can you then see why another functional protein may be a short distance in sequence space from another?