"As far as levers and bolts go, a lot of them have sensors monitored by software for stress."

That's in the far minority of situations. As part of my ME curriculum, I've worked with these types of sensors. It's very rare you'll find them monitoring bolts and levers.

It's true that software is extremely pervasive, however I believe you're overestimating the critical nature of it in most applications. Cars, bridges, buildings: Most critical failure points are mechanical. There's certainly a lot of software the goes into regulating a car, but if there's a failure in either the software or mechanics of the car, mechanical failure will most often be the more serious issue.

> Most critical failure points are mechanical.

Given that many mechanical and structural components are designed with the assistance of software that analyzes the stresses they are subjected to (and sometimes little or no analysis is performed beyond software simulation), one might question if it’s even possible to underestimate the role of software.

You make an excellent point. Though I think that the 'responsibility of an engineer' that is discussed in regards to the Iron Ring relates to it. It's up to the engineer to ensure that his design is sound regardless of any other factors.

You can't take a static view of the situation. More and more mechanical linkages are moving to microcontrollers, software and actuators.

The point is that software is an ever-increasing percentage of the most common items around us and as a result, its impact on our lives grows every day.

mechanical failure will most often be the more serious issue When the software is so tightly interlinked with the sensors and mechanisms that they are otherwise useless, you can no longer make that statement.

"they are otherwise useless" That's simply not the case for the most common mechanical components or engineering constructions. Bridges are fully functional without software. The same goes for buildings (and the majority of components that make up a building including stairs, doors, windows, walls, floors, thermostats, lighting, etc.). Even cars, which have software integrated to regulate many functions are still driven primarily by basic mechanical functions (ignition, combustion, power transmission, suspension, power generation via alternator, etc.).

At a more fundamental level, all components related to mechanical advantage that are so prevalent in our lives, yet mostly forgotten (gears, screws, levers, pulleys, wedges, etc.) are not being replaced by microcontrollers or actuators. You'd be hard pressed to find a better software+electronic component solution to solve the problem that the screw solves.

I assure you, I love software far more than I've ever loved mechanical engineering, but it's naive to think that it will overtake (or even come close to being more critical than) fundamental mechanics. Aside from information and communication, software only serves as a proxy for control over our physical world. I guarantee you that if you were to take a look around, the amount of pure "stuff" derived from basic engineering greatly dwarfs that derived from software.

While we could live in a shittier version of our world without software, we couldn't live in a world without traditional engineering.