Isn't it even counter productive ?
You limit too much the number of iterations because the shader is complex and take more times.
What force you to do an intensive denoising, because there were really too few iterations.
What lead you to a result near to what you would have had without the shader, but you'll need more time for this.
I think there is 2 brackets. People that have (really) a low card and trying to take advantage of it. I can kinda get it, even I'm no fan of it (there is often plenty of other thing to do first, I used a 1060 for years). And people that use it with no consideration, like they found the Graal or something. The later is tad bit annoying, not just with Daz/Iray - but also Cycles as well.
Where it's counter productive imho, it's people - no matter how bad short comings they have in general (lightening, surfaces management, composition), they don't care : I'll wash it with mister denoiser. Everything (along bad ideas) fits as it open the door to terrible habit imho.
It is also counter intuitive in a sense that rendering game is generally 'milking' the shit out of every surfaces. That's why you want say those 8k/16k huge ass detailed maps and those micro details everywhere. You want to min-max every tiny bit of it, that's the end game. Especially in porn/erotic slide show where human skin (and their complex shader) are front and center. Using a denoiser ain't gonna help you much, in fact it's working against you (and worsen even with Daz as Iray implementation offer no buffers for denoising such as albedo or bump/normal).
Now denoising has its uses (especially when animating) or can save time on hard surfaces (say a car paint) or more complex surface/effect (say caustics). Hence the parsimony part. Generally speaking, any destructive behavior (denoising, downsizing maps, hard edit and so on) should always be carefully considered (works with any rendering engine). Wallah I speak way too much for a sunday.