Because of course, iPhone sales tanked after Apple pulled the headphone jack, right? (In fact, Apple set a new record for iPhone sales in the device's first full quarter on the market.)
This isn't to say there isn't some pushback on removing the headphone jack, but it's probably a considerably smaller contingent than you imagine it is. One of the things I've learned about tech: the group that insists established technology X must remain forever is usually vocal far out of proportion to its actual influence. That's not to say that everyone else is enthusiastic, but they adapt, move on, and realize that the change isn't the end of the world like that handful of people claim it is.