Well, a physical open/close switch that's in line with the microphone lead would do the same thing. But, obviously that would be assuming privacy needs are incorporated into the design. I would imagine this could be added on some older laptop models with more physical space(I'm thinking of older thinkpads), but it would be a non-trivial process of opening a case, adding a cut-out for a switch, etc.

To be analogous, it would have to actually interfere with the thing-being-sensed. The idea is that it should work despite you having no knowledge, and being completely untrusting, of what shenanigans they might have regarding how it's wired up.

> It is a low-cost, low tech way to verify that the camera is not picking up usable images.

It is definitely not low cost.

In the hardware business, we count pennies. We count fractions of pennies with the costs of various components.

A shutter means at least one extra mechanical part, and a more complicated housing and increased assembly time at the factory.

You might look at a piece of plastic and think it is only a few pennies of plastic. But by the time you get it integrated into the product, and shipped out to consumers, it can add up to a dollar of cost. That really eats into the profits of low-margin hardware.

Only if enough consumers care about hardware shutters does it make business sense to include it. If most don't, and it is not a part of their buying decision making, then you're just throwing away money. Especially if it leads to increased post-sales tech support costs: ("My camera doesn't work! Is the shutter closed? Oh it is!").

Note that this is not an argument not to have hardware shutters. They are a good thing. But they come at a significant (to the final price) cost.

I would consider it a non-standard usage of "low cost" to apply it to case of something that provides an important function for 1/1000th of the cost of the product.

In any case, I don't think that's relevant to my point: I specifically said "important for laptops to permit a physical slider to block the integrated camera". That phrasing was deliberate: you don't want to trust the OEM's slider in the first place, just be able to add you own.

So, am I addressing a strawman? What OEM impedes you from adding a slider? Well, actually, Apple says it's not recommended to use a webcam cover because of how they designed it. That is poor design and security practice.

https://news.ycombinator.com/item?id=23795163

Or you can spend a dollar on a stick-on sliding camera cover, which is what I use on my Macbook. Or spend a fraction of a penny and tear a corner off a sticky-note and past it over the camera.