Mrs. Majuki encountered her first instance of DCC by herself this evening at a Starbucks in Taipei. She said the opt out was easy enough, but again this was on a contactless transaction with a signature waiver. If DCC wasn't an easy opt out here, I might be inclined to avoid tapping a card in favor of a chip-and-signature transaction in case there was forced DCC.
What's curious is that at two other Starbucks locations there was no DCC.