I do use a contactless Clipper card, on my phone. I don't think this bit is relevant: getting Visa to correlate transactions is probably a lot easier for Waymo to get done than integrating with Clipper to see if you've ridden transit in the past two hours. That's the same if you use a physical card or one on your phone.

I didn't disagree with you. I'm saying the key findings in that Clipper 2.0 postmortem were much bigger than any single incentive program like this Waymo one would have been. Hence I can see why Waymo avoid integrating with Clipper.

It said "one of the most complex fare payment systems in the world: 22 different transit agencies across nine counties in the Bay Area... [with thousands of fare categories]" And it's a single-bidder $500m contract that was 3 years late.