> The thinner the laptop, the more stuff I can cram in my carry on. ymmv

This is important. Because all those adapters do take up space.

A couple USB-C pigtail adapters take up nearly zero space, and everything will be USB-C in the near future.

But so do a couple millimetres of extra depth.

This means you're probably not using the laptop as a workstation. Say, graphics, CAD, CAM, video or audio authoring.

To do these you might want extra ports for say audio interface, specialized controller, digitizer... And a video output to present the results perhaps.

Instead you get to carry that and an interface box.

More disk space and RAM are major assets too.

Not that i wouldnt agree with you but when you are doing music production you will need powered hub anyway. At minimum i plug in mouse, soundcard, midi controller and most of the time keyboard and midi keys.

This is problem on every laptop since most of them have under 4 usb slots.

I do use it as a music workstation - external monitor, audio interface, a bunch of midi devices, external disks, ethernet, etc.

I plug all of this into the laptop with a single cable, via a thunderbolt dock, and it's the greatest thing ever.

If I'm carrying around a bunch of equipment for work on the go, throwing in one or two small usb hubs [0] is no big deal.

[0] https://www.anker.com/products/variant/USB-C-to-4-Port-USB-3...

2015 MacBook Pro - 0.71 x 14.13 x 9.73 = 97.6 cu in

2017 MacBook Pro - 0.61 x 13.75 x 9.48 = 79.5 cu in

The difference is 18 cubic inches, about the size of a 2 1/2" cube. I personally would take a few more hours of battery life, 32GB memory, SD card slot, etc in exchange for that volume on my carry on, even if I traveled as much as once a week.

n=1 disagreement on the keyboard. My hands can't find their way around it. I thought it would be fine - there are nubs on the F and J keys as normal - but the the lack of tactile sensation between the keys means I can't easily find the ~ key by touch. I've hit 1 and Tab more times than I have the ~ key, because I'm off by an amount which would be detectable and correctable if there was a tactile difference between keys. Similarly, the arrow keys are not easily found without looking at the keyboard for the exact same reason.

I can and have gotten used to the lower profile keys, but the lack of a tactile distinction between the keys makes a big difference.