I can totally see why gaming engineering would be harder than data science. I took some gaming development classes and found it to be quite challenging even when using engines like Unity that streamline a lot of the work. 

I can also see why middleware engineers would make more money. It requires really specific skill set: Physics, math, graphical programming, low-level coding, etc

DS is only hard (in technical aspects) when working in specific problems, mostly academic/research subjects. Most industry problems will not require advanced statistical modeling 

Data jobs are high paid imo because a) It's a new and growing field that take a while to create even entry-level workers (unlike software engineering which is more hands-on) and b) Computer Science majors struggle with statistics and math, while math/statistics majors struggle with software engineering, so someone with both skills tend to be highly valued from what I see 

My sense is that stuff like Nanite, Lumen, and Virtual Shadow Maps look great, but they can be resource hogs on current console hardware, especially when devs push for 60fps.

You can get a UE5 game looking great on console, such as Split Fiction, Hellblade II, Clair Obscurr, etc, but all too often devs layer on the expensive effects and lean too heavily on image reconstruction to shore up the results, leading to games that look ugly.

For the programmers doing the grunt work maybe, but for the devs in charge, it's their own fault for trying to make everything so unnecessarily big and complex and ambitious and biting off more than they can chew. Trimming the fat and going for more focused experience with a tighter scope would go a long way to alleviating this.

Right. These days, those are the 1 in 100 (i.e Epic's well-paid SWEs) who are game engine engineers and maybe some indie developers who are writing low-level (or near it) code on the CPU/GPU. 

Although that doesn't take away from the complexity of UI engineering, scripting, and other aspects of games either. Just that the best of these areas can be better paid in other industries and likely flee to those other industries as they gain experience and want to make more money. 

Yeah the hardest parts of the data science role, in my opinion, is the soft-skills and business-knowledge DS require to be successful. Though I do think there are some technical challenges that arise often in the role too, that just aren't as apparent because people (who aren't data scientists) don't quite know what makes a DS "good" or "bad" at the job. You can be a mediocre data scientist who just tries to throw well-performing models at business problems that the models aren't well suited for and doesn't really consider out-of-distribution contexts, and for which interpretability of the model is a nightmare to the point of not adding value to the stakeholders or a decent data-scientist who knows when and where to use certain tools and how to report the results in an understandable manner.

Data Science is just a lot more open-ended of a role than most non-analytical Software Engineering.  

Developers rarely determine the scope of a project (although their input is considered to an extent.) Designers (often with the input of the publisher these days) are the ones who do that. 

Designers are "developers".

They should start making games in cell shaded graphics going forward, maybe that will help

This is not traditionally how these words are used, no. Designers are part of a software development company, but they aren't developers in so much as they are solely performing the designer role. And not all (actually, very few these days) designers have a history as a developer. Many game designers have not written any code and have very superficial ideas of computing constraints. It is their job (in part) to know these constraints, but that is an ideal rather than a practical reality. 

"Developer" is shorthand for the studio, the whole team. Not just the programmers.

It also refers to a specific role in the process of game production.  

Here is an example. 

https://www.indeed.com/viewjob?jk=3597939b909cff88&from=shareddesktop_copy

We are seeking a passionate and talented 3D Game Developer to join our growing game development team. You will help build immersive, interactive 3D games using Unity (C#) or Unreal Engine (C++), working closely with designers, artists, and senior developers to create engaging experiences for PC and console platforms.

The other point made is that the publisher is often involved in the design process, and that is often a separate company. Often developers have their hands tied (those who perform the developer role and the organization as a whole.) 

I was using it as in "Retro Studios are the developer of Metroid Prime".

Publishers can set parameters, sometimes unrealistic ones sure, but I doubt they're specifically forcing devs to cram every demanding effect in the book into their games until performance tanks.