I have moved from genuinely wanting to buy the new MBP pre-announcement due to technical reasons (battery life, screen) to only needing to buy it due to iOS development lock in. Reminds me very much of the process I went through with Windows based PCs (except back then it was gaming).
I think I'll just go back to a Linux laptop (all other boxes are so the laptop has always been the odd-box) and will say goodbye to the iOS world. I mostly do web anyway and can live with non-native or no Apple apps at all.
Fellow iOS dev here. I had a similar sentiment first, but this new MBP is a very fine machine. It's blazing fast and I don't need a touchscreen (I might even buy a touchbar-less version if they made one at 15"). The dongle thing will resolve itself in the next 2 years, with more peripherals going wireless or replacements with USB-C ports.
Will you really let go of Sketch and all the other great tools from 3rd party devs just because you don't like dongles & touchbar?
I think I'll just go back to a Linux laptop (all other boxes are so the laptop has always been the odd-box) and will say goodbye to the iOS world. I mostly do web anyway and can live with non-native or no Apple apps at all.