I really didn't care about the port, so it did not affect my decision to buy the phone. I believe they left the port out to make room for the haptic feedback engine (or whatever they are calling it). I don't know that the trade off for most people is worth it, but the old button on the phone would wear out and now they don't have to worry about that issue.
In my world, Bluetooth is not a direct competitor to wired headphones. It works as a convenience. I have a pair of Parrot Zik 2.0 headphones and they have an app that gives you all kinds of control over everything from EQ to how much external noise you get. They don't sound as good as decent wired headphones, but I find them more convenient. For wired headphones, I have been using an external DAC for years via the lightning port (and the old port before that) and it works for me. I also prefer Airplay at home and Bluetooth on the road and at work, so Bluetooth is definitely my most used method of listening to music.
Someone mentioned the lack of optical output in the MBP and I am disappointed by it, but I never used it on my old MBP. I am hoping that their desktop Macs don't follow this trend since I do use optical out on my old Mac Mini. I have the new MBP and don't really mind using dongles on occasion. I have one USB-to-USBC, one HDMI to USB-C (still haven't used it, but will be nice for travel) and one thunderbolt 3 to thunderbolt 2 and they work for all of my needs. I really wanted the speeds of thunderbolt 3 that products will eventually take advantage of. These type of ports add tons of future capabilities that you can't get from old ports. The fact is that all of the USB-C ports are backward compatible with pretty much anything they had in the old Macs, while still offering huge speed advantages for future products. Yes, we have to deal with dongles for now, but for my daily use, it is a small price to pay and not really the big deal that everyone makes it out to be. I think they could have thrown one USB-C to USB adapter in the box, but it was only $9 to add it (probably cheaper from third parties now), so not really a deal breaker.
(as a side note, I believe the new MBP is overpriced and underpowered for some uses. I got the Mac for my birthday, so price (for me) wasn't an issue. The thing has plenty of power for my needs. It will be a long, long time before I have a real need for 32gb of RAM)