The answer is AMD/AMD, regardless of whether you're going for integrated or discreet. Reasons being stability and performance/price ratio. Stability because AMD's open-source drivers are excellent and rarely break with updates (not that it doesn't happen, but the breakage isn't as frequent as nVidia, statistically speaking). Plus, AMD drivers play better with Wayland compared to nVidia (although in saying that, nVidia has made some significant advancements in Wayland support recently, but may still require some custom variable settings/tweaks).

Laptop and GPU don't really belong in the same sentence. There are good ones that are integrated or not. But if you are asking about GPUs it's time to look into a desktop. A laptop will never have a good GPU.

Edit: Saw that you are talking about game development. Yes, it's desktop time. You will need it.

I have an Asus TUF with an iGPU and a discrete nVidia GPU. I did no configuration whatsoever to get the iGPU to work, and simply use prime-run when I need more GPU power (basically, only for Steam and Kdenlive).

I use Arch btw, on Xorg, with the closed-source nVidia driver (I never tried Wayland on this setup).

Onboard Intel/amd? “Discrete” Intel/amd/nvidia?

I have two laptops of this sort in use currently: One is a more recent AMD (5600H) + Nvidia (3080) and the other is an older Intel (some 10th-gen mobile) + Nvidia (2070). Both combinations work fine without any particular fiddling, apart from installing Nvidia proprietary drivers, on mostly any recent distro.

My use case is general desktop usage, Rust / C development, and occasional Steam-based gaming on these machines. Both laptops run pretty much the same as they did on Windows (GPU-wise). Fedora seems to work the best for me with everything setup nicely out of the box barring non-free stuff required from RPMFusion. On the Intel + Nvidia one, which is my distro-hopping laptop, I have used pretty much all distros without issue as well. Nix is however not included in the list of distros I have tried, but Arch is.

@PuppyOSAndCoffee I have a laptop with an Intel GPU with Iris graphics. Initially it was a huge pain to get it working as the kernel version to support it hadn't been released yet. However, NixOS gave me enough freedom to set my kernel version to a release candidate that fixed it. Now that they've rolled the new kernel into the main nixpkgs the graphics work fine.

And for what it's worth, my desktop with an nvidia gtx1080 works just fine with NixOS (at least for casual gaming) by allowing it to run unfree software and telling it to use an nvidia driver.

I recently switched away from the Legion 5 15ARH05: AMD APU+NVIDIA. The thing with laptops is that you are at the mercy of the system integrator. They are able to integrate the GPU in weird ways and often do. For me the external monitor wouldn't work without the proprietary NVIDIA drivers installed. The NVIDIA drivers caused all sorts of problems, from backlight woes to failure to resume from standby (which worked fine without the drivers installed).

If you do go with an NVIDIA machine, go with one that is built for Linux. I switched to an all AMD (I really don't want to deal with NVIDIA bullshit) System76, but I hear their NVIDIA story is pretty good.

Do not buy a Windows+NVIDIA laptop and put Linux on it - unless you get a glowing recommendation for a specific model.

You should install the open source System76 modules for the best experience (not required): https://github.com/NixOS/nixos-hardware

Have got an Nvidia quadro in my laptop, Wayland on Nvidia still kinda sucks but if you run the DE on integrated graphics and intensive stuff on the GPU it works a charm