It is a bit silly but I think it just helps with code readability some people.

I personally don't use it too, but I think it's origins are not just readability, but from developing queries in a REPL like environment.

As you develop and are constantly creating / debugging queries where you often add new and or or clauses as a whole line, that becomes much faster to add and remove those same lines as they're a single shortcut away in nearly all text editors.

For their one here it's just the ability to rapidly comment/uncomment conditions in a query editor while exploring the data or debugging the query, and not having to worry about the leading AND or OR.

I've also seen it in code with iterative adds, for example:

  for crit in criteria:
      sql += " AND " + crit

No needed to add a sentinel or other logic to skip the first AND. I saw it a lot before people got used to " AND ".join(criteria).