I recently posted a video of a residential job I do every 3 weeks. I started this job before I had a WFP and cleaned it with dawn and squeegee. As I got used to the WFP, I did a bit of both on exterior. Now, WFP only. With either 6 months, or 3 weeks in between, I can say that there has been absolutely no noticeable difference of dirt accumulation when comparing dawn with WFP.
My point, we can talk about this til the end of time but when it comes down to it, it’s technique that matters. Choice of soap is mostly preference.