When IT folks say devs don't know about hardware, they're usually talking about the forest-level overview in my experience. Stuff like how the software being developed integrates into an existing environment and how to optimize code to fit within the bounds of reality--it may be practical to dump a database directly into memory when it's a 500 MB testing dataset on your local workstation, but it's insane to do that with a 500+ GB database in production environment. Similarly, a program may run fine when it's using a NVMe SSD, but lots of environments even today still depend on arrays of traditional electromechanical hard drives because they offer the most capacity per dollar, and aren't as prone to suddenly tombstoning when it dies like flash media. Suddenly, once the program is in production, it turns out that same program's making a bunch of random I/O calls that could be optimized into a more sequential request or batched together into a single transaction, and now it runs like dogshit and drags down every other VM, container, or service sharing that array with it. That's not accounting for the real dumb shit I've read about, like "dev hard coded their local IP address and it breaks in production because of NAT" or "program crashes because it doesn't account for network latency."

Game dev is unique because you're explicitly targeting a single known platform (for consoles) or targeting for an extremely wide range of performance specs (for PC), and hitting an acceptable level of performance pre-release is (somewhat) mandatory, so this kind of mindfulness is drilled into devs much more heavily than business software dev is, especially in-house dev. Business development is almost entirely focused on "does it run without failing catastrophically" and almost everything else--performance, security, cleanliness, resource optimization--is given bare lip service at best.

Game development is a very specific use case, and NOT what most people think of when talking about devs vs ops.

I'm talking enterprise software and SaaS companies, which would be a MUCH larger part of the tech industry then games.

There are a large number of devs who think public cloud as infrastructure is ALWAYS the right choice for cost and availability for example... Which in my experience is actually backwards, because legacy software and bad developers fail to understand the limitations of this platforms, that it's untrustworthy by design, and outages insue.

In these scenarios understanding how the code interacts with actual hardware (network, server and storage or their IaaS counterparts) is like black magic to most devs... They don't get why their designs are going to fall over and sink into the swamp because of their nievete. It works fine on their laptop, but when you deploy to prod and let customer traffic in it becomes a smoking hole.