But whether you love or hate (as I do) the brown Noctua colours, the one thing is that they are kinda polarising. They're not a "clean fit" in any build unless you really wanna show that you use Noctua and use them as a centrepiece. Which I guess is the point of their marketing. They want to make it seem their fans are so good people are willing to put up with the colour.
They are going inside the computer where they aren't visible. The point of a computer to me is to be powerful while being as discrete about it as it can be (i.e. quiet and no blinking rgb lights). I don't have a glass side panel, I run an older Fractal case with aluminum sides with sound dampening instead.
I never understood "form over function", but each to their own.
Speak for yourself :) My computer is pretty open, the fans are visible through the front and through the side panel.
I don't run RGB either though but I do like to style it.
And of course the "form over function" is part of that market niche that really pays a lot for something like a fan. Noctua aren't that special, as others have mentioned there are much cheaper brands with the same performance including sound level. You do pay a lot for just the branding.
I have some Noctua fans still going strong after a decade. Are there other brands that can also do that? Probably, I have some BeQuiet fans now too in a tower CPU cooler (couldn't get hold of a Noctua cooler during the pandemic), it will be interesting to see what happens in another 6 years or so with them.
And no, I don't change my computer every 3 years or so any more, so longevity does matter to me.