Plain language
The APE question follows the traffic question.
If a project foreseeably changes traffic on historic streets, preservation review should ask whether those streets are inside the area where effects may occur.
Section 106 / Accountability
Preservation review is one accountability lens.
Section 106 matters where a public project may affect a historic district through indirect traffic effects. It is not the whole traffic story, but it is one way to ask whether downstream impacts were studied seriously.
Caution
This is a review lens, not a final finding.
The public argument should distinguish facts, evidence, inference, and advocacy. It should not be presented as an agency determination unless the record says so.