Pollen is abrasive and acidic
Those grains are hard, irregular, and slightly acidic once wet. Wiping a dry dusty car with a towel is essentially dry-sanding it, and letting the dust sit through a spring rain starts a mild acid etch.
The plan
Touchless rinse two or three times a week during the peak — never a dry wipe. Keep a sealant on the paint so the pollen has less to key into. Run the presoak long enough to float the grains off before any pressure hits them.
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