Replying to @kingjen and @montezumachavez, @PrivacyMaverick, @rcalo, @FTC, @Cristianapt
That's already the case! It looks uniform because it's never going to tell you that it's not, but most digital actors will target calls to action based on personalised predictions about how they'll perform.
Sometimes it's even done badly — that's when you notice most. For instance, I'm in a Twitter test in which the follow/following button looks alternatively hollow or blue but they've made it different on different devices and it's breaking my brain.