Are they out of their mind ?

I was fooling around minutes ago and I fall into that document:

Icons Sizes …

And that is only for Apple iPad (as far as I understand).

And what about Windows (UWP), Android, Linux, etc. ?

Edit: typos.

for iOS there are (to the best of my knowledge) 23 different required icon sizes (this covers @1x , @2x and @3x with a few duplicates in size, but not in @x)
for AppStore deployment there are 3
for Android there are 6 sizes
for Xojo there are 7 sizes
for macOS (non-Xojo) there are 10 sizes
for the Apple Watch there are 9 sizes

I discussed an App (a year or so ago) that I wrote that automagically creates high quality versions of all these required sized from a single large format graphic

but the simple answer to your question… Yes they are out of their minds.

From a programmer’s viewpoint, sure they are.
With the eyes of a designer, not at all.
iOS alone supports a multitude of devices with very different screen sizes and resolutions. How big should an app icon be? One that fits correctly onto an early iPhone screen would be way too tiny to be found on an iPad Pro. And vice versa.

On smaller resolutions/sizes, you will often find you have to simplify your drawing to maintain its readability. Much like hinting in PostScript fonts for the low resolution screens of former times. So from a perfectionist’s point of view scaling icons would not be sufficient.
Of course in many other cases it is. That’s where tools like Dave’s come into play.

If you design your icons manually, Affinity Designer is programmer’s friend. You can create vector images and define an output persona that automatically writes all the necessary files.

While I understand the basic need for various sizes of icons… at some point a level of compromise should enter the criteria.

For iOS has 57px and 60px , as well as 72px and 76px… is there that much “detail” is those 3 or 4px? that warrant a whole icon?
not to mention

  • 20@2x and 40@1x
  • 20@3x and 60@1x
  • 40@3x and 60@2x
    They have (and require) different names, yet they are the same size. granted you could have differnent images, but that is rarely the case