Did you file a complaint with Uber? As far as I'm aware, what that driver did is a violation of Uber policies (both canceling without a good reason, and waiting 10 minutes before said cancellation). I think that Uber should proactively check up on all driver cancellations, but they probably only check up on complaints, so go ahead and complain when that happens.
If people complain when their drivers cancel, drivers won't cancel anymore (without a valid reason). The only way they can get away with it is if you say nothing.
I wrote a really long complaint email and they "resolved" it by crediting my account with $20 credit. I ended up paying like $110 for that ride. It would have been about half at the 1.75x rate, and about a third without the surge pricing.
Uber never tells customers when they penalize drivers, so I hope you aren't assuming that the $20 credit was the sole response to your complaint. I expect that the driver was disciplined in some fashion, and that if they accrue repeated complaints for canceling they would be suspended (similar to how drivers that get repeated sub-5-star ratings do).
If people complain when their drivers cancel, drivers won't cancel anymore (without a valid reason). The only way they can get away with it is if you say nothing.