>No other branch of engineering, at least none that come to mind, have to deal with the number of variables that any medium-sized software application does. Software, being infinitely malleable and running on a seemingly infinite variety of hardware in an infinite number of environments, is vastly harder than any other engineering.

I'm not going to argue if this is right or wrong as I don't have a Software Engineer's perspective. My background is in chemical and materials engineering in heavy industry (mining and manufacturing sectors).

I've worked in Operations and Process Engineering positions (https://en.wikipedia.org/wiki/Process_engineering) and in more recent years I've been employed as a "Technology engineer" which is essentially integrating new technology and process improvements and optimizations into existing industrial applications.

The scope and complexity of what Engineers deal with daily might surprise you, software is complex so to is something like a smelter or refinery.

Pretty sure I can spend 15 min on Wikipedia and find dozens of engineering fields vastly harder than software engineering.

Also, your definition of software is really far from reality. 99% of software don’t have to deal with hardware directly and are compatible with a number of environments I can count on one hand.

There are engineers who have to worry about quantum effects that physicists barely understand. I think, by definition, that's harder than Turing-complete software.

Wast number of hardware and infinite number of environments is not contemporary issue with software. Contemporary issue is that software does not run properly even when it was meant to run at one specific piece of hardware, is often not tested at all, contracts are made for impossible deadlines and even software practices known for years are still not made (as much as management claims to do them to customers).