I think this will depend on the peripherals. When they removed the CD/DVD drive, it was at the cusp of moving software installs to using thumb drives or online.
With USB-C though, I can't help but feel they missed the mark on this. What is annoying about this is you will either have to replicate your cables or carry USB-A to USB-C converters. Peripherals haven't really fully embraced USB-C for the most part. The companies making the biggest gain are those that provide a USB-C dock that provides USB-A ports. It's kind of funny.
Lastly, the iPhone cannot be connected to a 2016+ MBP out of the box without a dongle... the synergy here is fantastic.
Carry a couple of USB-C to USB-A cables. You still have 2 USB-C ports available, with the 2015 you only had 2 USB ports, hell 4 USB-C to USB-A and you now have twice the number of USB-A ports you had on the 2015. HDMI/Display port/VGA/DVI, just plug the right cable in and you have whichever you want, no dongle, just the cable. The 2015 you would generally be stuck with the HDMI port and the mini display just sitting idle. You couldn't plug into a display port monitor on the 2015, you can't plug into a USB-C monitor with it, nor DVI or VGA, so you need special cables or an adapter. i.e. no different to the 2016. The cables cost around the same as a couple of coffees so not a big deal.
People keep repeating no good for pros. Look in the laptop bag of an IT pro, even those who use windows laptops, you will find a huge range of cables/adapters anyway, likewise for anyone who presents at conferences.
Yes you can connect an iPhone without a dongle, you just use a USB-C to lightning cable which Apple have sold since the 2016 was released. Mine is rarely used as I have plenty of A ports available at my desk (single cable gets those + monitor + network + drives + bluray). Most of the time I do not need to connect the phone directly via cable. I suspect most others are in the same situation. (Comes in handy for fast charging from the laptop power brick.)