Similar story here. I managed to spill coffee on my MacBook Pro 2015, which I had been really happy with -- great performance (max out with CPU, RAM and 1TB SSD).
I got the new 2017 model, and really hated the keyboard, but also really disliked the Touch Bar and lack of Escape button. I'm not at all concerned with the lack of USB or SD card reader, though I was disappointed with the lack of performance improvements over the 2015 model.
So I returned it, and bought a brand new 2015 model. Except it turns out they changed it! It no longer has a dedicated AMD graphics card. It's an integrated Intel Iris Pro with less VRAM, and it seems really underpowered compared to the old AMD Radeon on my previous model.
The lower graphics performance is especially noticeable if you turn the Retina setting to scaled (like 1.5x, which I prefer). It's not just that apps render a bit more slowly -- I get the sense that there's some GPU memory transfer bottleneck that's happening that causes sudden pauses in UI rendering across the entire OS. And it's something that makes the whole computer slow down with use; rebooting (or restarting Safari) speeds things up again. Typing in Slack or VSCode has noticeable lag, and switching between Spaces results in a significant pause, and the switching animation stutters something fierce. I would go so far as to say that scaled Retina is unusable on this model.
I looked the model ID, and it's "MacBookPro11,4". The model that has a dedicated GPU is "MacBookPro11,5" and was discontinued in October 2016. So it looks like it's impossible to get a 2015 MBP with a dedicated graphics card right now. You can't plug in an external GPU, either; while High Sierra now supports it, it's only supported on the newer models via Thunderbolt 3.
This is really frustrating. I've been using Apple laptops since 2006, and this is the first time when I can genuinely say that none of their products are good enough. I've even looked at the possibility of switching to a Linux laptop, but Linux distros are nowhere near macOS in terms of cohesiveness and UI, and while the laptop models I've looked at (ThinkPad T480S, Dell XPS 15, System76 Oryx Pro) admittedly have much better specs than Apple, none of them stand out as being particularly good.
I'm now hoping that Apple will see sense this year and offer a non-Touch-Bar model with some kind of non-butterfly keyboard. But I'm not hopeful.